ISSN:0003-2654    

DOI:10.1039/AN96186FX021

出版商:RSC    

年代:1961

数据来源: RSC

ISSN:0003-2654    

DOI:10.1039/AN96186BX023

出版商:RSC    

年代:1961

数据来源: RSC

ISSN:0003-2654    

DOI:10.1039/AN96186FP095

出版商:RSC    

年代:1961

数据来源: RSC

ISSN:0003-2654    

DOI:10.1039/AN96186BP109

出版商:RSC    

年代:1961

数据来源: RSC

摘要:

MAY, 1961 THE ANALYST Vol. 86, No. I022 PROCEEDINGS OF THE SOCIETY FOR ANALYTICAL CHEMISTRY ANNUAL GENERAL MEETING THE eighty-seventh Annual General Meeting of the Society was held at 2.15 p.m. on Friday, March 3rd, 1961, in the meeting room of the Royal Society, Burlington House, London, W.l. The Chair was occupied by the President, Mr. R. C. Chirnside, F.R.I.C. The Financial Statement for the year ending October 31st, 1960, was presented by the Honorary Treasurer and approved, and the Auditors for 1961 were appointed. The report of the Council for the year ending March, 1961 (see pp. 286-297), was presented by the Honorary Secretary and adopted. The Scrutineers, Mr. H. E. Brookes and Mrs. H. I. Fisk, reported that the following had been elected officers for the coming year- President-A.J. Amos, Ph.D., B.Sc., F.R.I.C. Past Presidents serving on the CounciLR. C. Chirnside, J. H. Hamence, D. W. Kent- Vice-Presidents-A. L. Bacharach, J. R. Edisbury and F. C. J. Youlton. Honorary Treasurer-D. T. Lewis. Honorary Secretary-R. E. Stuckey. Honorary Assistant Secretaries-C. A. Johnson (Programmes Secretary) and S. A. Price. Other Members of Councid-The Scrutineers further reported that 469 valid ballot papers had been received and that votes had been cast in the election of Ordinary Members of Council as follows-D. C. Garratt, 386; D. W. Wilson, 355; S. G. Burgess, 283; S. H. Jenkins, 272; R. A. Chalmers, 266; C. A. Parker, 247; A. G. Jones, 243; C. W. Herd, 230; N. R. Jones, 201. The President declared the following to have been elected Ordinary Members of Council for the ensuing two years-S.G. Burgess, R. A. Chalmers, D. C. Garratt, S. H. Jenkins, C. A. Parker and D. W. Wilson. D. M. W. Anderson, B. Bagshawe, E. Bishop, E. Q. Laws, W. M. Lewis and J. T. Yardley, having been elected members of the Council in 1960, will, by the Society’s Articles of Association, remain members of the Council for 1961. J. Markland (Chairman of the North of England Section), A. F. Williams (Chairman of the Scottish Section), G. V. James (Chairman of the Western Section), H. C. Smith (Chair- man of the Midlands Section), C. Whalley (Chairman of the Microchemistry Group), G. W. C. Milner (Chairman of the Physical Methods Group) and J. S. Simpson (Chairman of the Biological Methods Group) will be ex-ojicio members of the Council for 1961.The retiring President, Mr. Chirnside, thanked the Honorary Officers for their services to the Society during his term of office, and especially Dr. Amos, under whose Honorary Treasurership much progress has been made. He then formally installed Dr. Amos in the Chair. After the business outlined above had been completed, the meeting was opened TZ visitors, and the retiring President delivered his Presidential Address (see pp. 314-324). Jones and K. A. Williams. DEMONSTRATION MEETING A DEMONSTRATION Meeting of the Society was held at 6 p.m. on Wednesday, March 29th, 1961, at Chelsea College of Technology, Manresa Road, Chelsea, London, S.W.3. The demonstrations were of laboratory-made equipment, and the following pieces of apparatus were shown- Small-scale methods of heating and stirring, and miscellaneous small-scale techniques- 277 M.A. Fill (Norwood Technical College).PROCEEDLNGS [Vol. 86 278 Apparatus for alkaline isomerisation of fatty acids--I>. M. Morgan (St. Mary’s Hospital). The apparatus provides a means of heating the isomerisation tubes under nitrogen a t a controlled temperature of 180°C (Holman, R. T., and Hayes, H., Anal. Chem., 1958, 30, 1422). The apparatus is designed for the analysis of gas samples of volume 1 t o 4 ml. Semi-micro Orsat apparatus-R. Moss and A. Slater (The Associated Ethyl Co., Ltd.). The gas burette is connected t o two reservoirs by a three-way U-bore tap. This obviates the need t o raise and lower the reservoir and gives precise control of the movement of the sample between the gas burette and the absorption pipettes.Multiple stirrer unit for coagulation tests on water-K. F. Packham (Water Research I t has a built-in illumination system, two stirring speeds and a device that permits all the samples t o be dosed with coagulant simultaneously. Simple apparatus for continuous sampling of water-R. F. Packham (Water Research Association). The unit is designed t o accommodate l-litre samples. Association). A series of collecting cups machined circumlierentially in an aluminium table connect to the A tube delivering a continuous flow of water is moved in a circle so that each of the sample bottles. cups is fed in turn. The apparatus is set up t o collect 24 hourly samples. The following exhibits were demonstrated by J.E. Still and J. H. Konrath (G.E.C. Ltd., Automatic integrator for gas chromatography. Hirst Research Centre)- (Designed by J. H. Konrath). The areas of the successive peaks of a chromatogram are integrated and registered on a digital counter with zero reset. A potentiometer rotating with the chart-recorder pen drive supplies a varying direct voltage to an integrating motor on whose spindle is mounted a light mica disc, partly silvered. The rotation of this disc interrupts a light beam falling on a photo- transistor, and this operates the counter through a relay. Atomiser for flame photometry, constructed entirely in a transparent plastic material. This all-plastic atomiser permits solutions containing hydrofluoric acid t o be sprayed. Another advantage of the mode of construction lies in its reproducibility; this feature leads to the possibility of using interchangeable jets of different tip dimensions t o provide a range of atomising characteristics. (Designed by D.G. Timms and J. H. Konrath). A robust katharometer of high sensitivity with replaceable coiled-tungsten filaments supported (Designed by J. E. Still). Tungsten-filament katharometer for gas chromatography. under tension. Sample-admission valve for vacuum fusion apparatus. (Designed by J. E. Still). This valve provides for the admission of solid samples into a high-vacuum system without The use of a lubricated seal, which could contaminate the sample, is release of the vacuum. avoided. Methods for quantitative assessment of psychotropic activity in mice-M.W. Parkes (Roche Psychostimulant agents are estimated by (a) measurement of tremor in mice placed in canisters on gramophone pick-ups, the output of which is conventionally amplified and fed to an integrating motor operating a counter; ( b ) measurement of locomotor activity of mice walking on silica gel granules in tins with microphones under the floor, the output from these being treated as in (a). Both psychostimulant and depressant agents may be estimated by rise or fall, respectively, in the body temperature of mice, measured by rectal thermistor probe (Designed by A. W. Lessin). An anticoprophagic cup-or “Faecol1ector”-for the rat-A. E. Render (Bovril Research Department). It can be (Designed by B. H. Doell.) A simple recording analytical balance designed fsor thermogravimetry-H.L. Evans and J. T. McAloren (Directorate of Chemical Inspection, War Office). The balance has been constructed from an old free-swinging balance and operates on a simple hydrostatic principle. Electronic equipment is reduced to a minimum, is of simple design and transis- torised. By simply changing the hydrostatic floa.t, the balance may be made t o operate over three ranges of weight change. These are (2) 0 to 150 mg, (ii) 0 t o 50 mg and (iii) 0 to 20 mg, over a chart length of 10 inches. It is fitted with an oil-bath heating furnace designed for medium-temperature thermogravimetry, with a linear rate of heating as, slow as 0.5” C per minute. Thermograms of oxalic acid and styphnic acid are shown. Products Ltd.). A light aluminium cup is fixed over the tail of the rat t o prevent i t eating its faeces.emptied without removing the device, so avoiding trauma t o the tail.May, 19611 PROCEEDINGS 279 “Su1phometer”-J. B. Clegg (The Permutit Co., Ltd.). A device for turbimetric measurement of sulphate concentration (range 0 to 60 p.p.m.) in natural waters; barium chloride, hydrochloric acid and gelatin are used as reagents. Humidator Cells-H. E. C. Powers (Tate & Lyle Ltd.). Two cells designed to facilitate operations with vapour-pressure-sensitive systems. The enclosed atmosphere is maintained a t the desired level by the presence of suitable salts or solutions. In the smaller cell progressive changes may be observed by transmitted light and photographically recorded. Although designed for the study of crystallisation in thin films, the apparatus obviously has a wide range of possible applications, including even non-aqueous vapour-pressure operations, permitting molecular migration to equilibrium (Nature, 1960, 188, 289; New Scientist, 1960, 8, 1178; Int.Sugar .I., 1960, 62, 307). Semi-automatic compound dilution pipette-R. R. Goodall and W. Taylor (Imperial Chemical Industries Ltd., Pharmaceuticals Division). syringe is filled to a stop-screw via tap A from a gravity head. sample by suction through tap B. the contents of the syringe flush out the contents of the capillary pipette. can be varied. the observed precision was 0.3 per cent. A syringe is connected via two two-way taps A and B to a capillary pipette set below it. The The capillary pipette is filled with Taps A and B are then turned to the discharge position so that The volume of the syringe The apparatus is especially suitable for serial dilution, and on a 1 to 17.5 dilution Method for obtaining weighed micro samples of moisture- or oxygen-sensitive compounds An electrical arrangement for sealing a micro sample of liquid in a capillary tube, applicable (Designed -Miss I.Hall (Imperial Chemical Industries Ltd., Nobel Division). to the micro-sampling of materials sensitive to atmospheric water vapour or to oxygen. by A. F. Williams and T. R. I’rentice; see Analyst, 1960, 85, 126.) A.R.D.E. card sorting/punching machine-R. J. Loneragan (Armament Research and Development Establishment). A card-sorting and punching machine for edge-punched cards. No special pre-punched cards Assay of antibiotic mixtures using electrophoresis in agar- J.W. Lightbown and P. de Rossi A mixture of two antibiotics of unknown concentration is placed with a mixture of standard preparations in punched holes, in a Latin Square design, a t several dose levels, in a slab of buffered agar. After electrophoresis for a short period (e.g., 5 to 10 minutes) the slab of agar is seeded and incubated. Apparatus for electro-chemical plating of polonium-210 on nickel-Mrs. M. P. Taylor (Medical The solution Punched-card index of analytical bibliography-D. R. Curry and P. J. Moore (Overseas The index, which utilises single-sided Analytical Abstracts, is based on a novel punched-card system. Selected abstracts are indexed according to elements determined, method used, author, journal, etc.Considerable cross-referencing is possible without adding to the bulk of the system. In searching the index, the abstracts of all relevant papers-whether in a wide or narrow field of enquiry-can rapidly be produced for inspection. Present capacity of the system is 5000 abstracts. A similar system is in use for recording samples received by the laboratory, details of analysis, etc. Induction heating applied to the micro-determination of carbon and hydrogen-Mrs. D. Butterworth (National Chemical Laboratory). A radio-frequency generator is used as a source of heat for volatilising thermally-stable compounds in the rapid method for determining carbon and hydrogen. Agar-gel plate immunoanalysis- J. G. Tieinberg and Miss A.Temple (Beecham Research Laboratories Ltd.). Special cutters have been designed and constructed for producing standardised well patterns in agar-gel plates. The plates are used for the qualitative and quantitative assay of macromolecular substances by serological precipitation in the agar-gel matrix. The cutters can be made in an instrument shop and are also now available commercially. are required. Punching and sorting are carried out on the same keyboard. (National Institute for Medical Research). Independent assays are obtained for each antibiotic. Research Council Radiological Protection Service). The apparatus consists of eight de-mountable cells, each containing a nickel disc. containing the polonium is continuously agitated by means of a stream of air.Geological Surveys). Magnetically driven fan-R. J. Jackson (Beecham Research Laboratories Ltd.) , An internal fan in a sealed humidity cabinet is driven magnetically from outside the cabinet.280 PROCEEDINGS [Vol. 86 Electrodes and cells for polarography-Mrs. B. Lamb and Mrs. D. Konczak (Evershed Rotating solwtion for use with solid electrodes-The base on which the vessel rests is rotated to This equipment may also be used with stationary Hanging-drop electrode-Hanging drop as described by Professor Kemula. Vibrating electrode-The vibrating electrode is designed for the measurement of dissolved oxygen and also as an indicating electrode in amperometric titrations. It is based on the original design of Dr. Lindsey. The frequency is 50 cycles and the amplitude may be varied between 0.4 and 2.0 mm, but the exact amplitude will depend on the weight of the electrode. It is also possible to combine this vibrator with a silver - silver chloride electrode as shown.Further, i t may be mercury plated for enhanced sensitivity with respect to oxygen. Flow-through cell-A simple flow-through cell with constant-head device arranged as a polaro- graphic cell to permit measurements to be made on a flowing solution. The conventional dropping- mercury electrode is used as the cathode and a pool of mercury as anode in this exhibit, but a solid electrode could be used as indicating electrode if desired. and Vignoles Ltd.). provide efficient stirring for amperometric titrations. solid electrodes. The following exhibits were demonstrated by E.Bishop (Washington Singer Laboratories, Automatic pre-heating self-flushing water :;till-R. G. Dhaneshwar and G. D. Short An all-glass/quartz still with high reflux ratio and heat conservation, producing a sterile grease-free water of parts per thousand million purity, with automatic fail-to-safe operation, and which can be mounted high on a wall, out of the way. University of Exeter)- (University of Exeter). Potentiometric titrimetry-R. G. Dhaneshwar and G. D. Short (University of Exeter). A simple low-impedance apparatus assem bled from radio components for routine use and teaching; a single meter, used as both null detector and voltmeter, allows potential measure- ments to be made with a precision of 0.1 per cent. without calibration. Facilities are included for polarisation and dead-stop titrimetry. Differential electrolytic potentiometry-R.G. Dhaneshwar and G. D. Short (University of Exeter). Automatic electrochemical differentiation of potentiometric curves. A versatile research assembly for the study of current - potential relationships a t electrodes in the current range of 10-5 to 10-16 amp, with ballast resistors from 10s to lOI3 ohms, a variety of electrodes and facilities for the simultaneous study of the behaviour of individual electrodes. Needle-valve weight burette-R. G. Dhaneshwar and G. D. Short (University of Exeter). A 60-ml burette of minimum weight, obviating the use of lubricated taps, yet capable of precise manipulation and of delivering increments of the order of 0.001 ml. Microcoulometry-E.Bishop (University of Exeter) . Conventional constant-current coulometry applied to small samples a t high dilution. With the electrode-platform type of micro-cups, capillary-lock auxiliary electrodes and location of the end-point by D.E.P., determinations of equivalent of oxidisable matter have been made. Electronic constant-current/constant-potential source-E. Bishop (University of Exeter). A simple, fairly conventional constant-po tential supply of low output impedance, having a constant current output through a constant electronic resistance, based on cheap surplus valves, and regulating to 50.02 per cent. with a time-constant of 10 microseconds. The following exhibits were demonstrated by F. Albert-Recht (Clinical Chemistry De- partment, Edinburgh University)- Rocking extractor.The instrument agitates 2-phase solvent systems contained in globular separating funnels by a rocking-pendulum movement. The gentle agitation assures adequate extraction, and formation of emulsions is minimised. Ultrafiltration apparatus. The instrument achieves ultrafiltration a t high pressure (150 lb per sq. inch) through a length It provides speedy handling of relatively large volumes of colloidal of “Visking” cellulose tubing. solutions. Concentrated colloid and ultrafiltrate are available for subsequent analysis. Sample cell arrangement for E.E.L. flame photometer. A sample cell combined with distilled-w ater flushing and suction-emptying arrangements This combination speeds up the handling fitted on to a standard E.E.L. flame photometer.of samples and standards by efficient presentation of samples for spraying.May, 19611 PROCEEDINGS 281 Electrophoretic tank for small-scale cellulose acetate st rips. The electrophoretic tank with small strip chamber and thermally insulated walls keeps water The design of electrode vessels restricts movement of evaporation from strips to a minimum. decomposed buffer on to the strip. General-purpose integrating flame photometer-R. J. Webb and P. C. Wildy (U.K.A.E.A. Research Group, Woolwich Outstation). A flame photometer of high sensitivity with provision for integrating or direct reading, use of internal standards and automatic background correction. The instrument is now being used for the determination of strontium in calcium a t the 100 p.p.m. level, where the line - background ratio is 1 to 200.Woolwich Outstation). Anodic stripping polarography-A. Parker and E. A. Terry (U.K.A.E.A. Research Group, Controlled-potential electrolysis causes cations to deposit on a stationary mercury drop, and a Cadmium and lead can Anti-coincidence /?-scintillation counter for low activity levels- J. L. Waddingham and A thin plastic phosphor in contact with the sample is contain& in a well in a cylindrical phosphor, The two associated photomultipliers are connected in anti-coinci- The background for ,&counting has been reduced to 0-4 count per minute, and the efficiency reverse voltage sweep is then applied through a cathode-ray polarograph. be determined a t the M level. J. D. Rowe (U.K.A.E.A. Research Group, Woolwich Outstation).which counts external radiation. dence. a t the 2-MeV level is 50 per cent. Rowe (U.K.A.E.A. Research Group, Woolwich Outstation). and only coincident pulses are accepted. photomultipliers, since random thermal noise is minimised. Coincidence scintillation counting for low-activity levek- J. L. Waddingham and J. D. Scintillations from a thin phosphor in contact with the samples are viewed by the photomultipliers This arrangement permits high gain to be used on the A simple gas chromatograph-C. J. Barker (The Metal Box Co., Ltd.). A compact and robust apparatus, easily constructed in a laboratory workshop, operates a t tem- Detection is by thermal- peratures between 0" and 100°C and with columns up to 20 feet long. conductivity measuremcnts with a thermistor bead.J. R. Bishop and W. H. Hill (The Metal Box Co., Ltd.). (Designed by J. R. Bishop.) Apparatus for coulometric determinations of free tin and tin - iron alloy on tinplate- The tin coating layers are removed anodically in a cell made from a Tufnol cylinder. Changes in the potential a t the anode half-cell are recorded by amplifying the current flowing in a high-resistance reference circuit. Calibration is by a novel gravimetric technique. A simple illuminated box for the incubation of stock cultures of Ochyowonas maZhamensis without overheating-S. A. Price and L.' Gare (Vitamins Ltd.). Ochromonas cultures, used for vitamin-B,, assay, should be grown under artificial light a t 27" or 28" C, but temperatures only slightly higher than this inhibit growth of the organism.A bellows-type thermostat controlling the 60-watt lamp safeguards against overheating from the light source. Titration assembly for acidimetric microbiological assays-L. Gare and S. A. Price (Vitamins Cultures are titrated in a small beaker, magnetically stirred, the end-point being determined A magnetic amplifier feeds a recording milliammeter. Ltd.). with a pH meter and the contents of the beaker emptied automatically by suction after titration. Desiccator seal ring-P. R. Watt (Vitamins Ltd.). The device consists of a flexible annular ring fitted over the upper flange of a standard vacuum The seal is free from sticking and gives a greaseless joint: a t the same time both flanges As the lid lifts off vertically, the storage capacity of the desiccator.are protected from mechanical damage. desiccator may be nearly doubled. Automatic micronitrometer-P. R. Watt (Vitamins Ltd.). The apparatus is designed as a robust single unit to replace the conventional nitrometer and It is self-balancing and reads the gas volume No drainage period is necessary, and there are no errors due to drainage associated apparatus used in the Dumas nitrogen assay. directly on a digital counter. or etching. Semi-micro molecular pot still-P. R. Watt (Vitamins Ltd.). An all-glass horizontal still for molecular distillation of charges in the size range 0.2 to 0-5 g. The still, high-vacuum pump, trap and controls Up to six fractions may be collected from each charge. are mounted compactly together as a unit.282 PROCEEIIINGS [Vol.86 An inclined drawing board fitted with a roll of tracing paper for the repeated use of a single A roller supply of tracing paper is drawn over a fixed piece of graph paper and held in position Multiple graph records An illuminator-box for large plate microbiological assays-P. G. D. Naylor (0x0 Ltd., piece of graph paper-P. G. D. Naylor ((0x0 Ltd., Oxoid Division). on an inclined drawing board by polyurethane-f oam-coated metal bands. can be plotted by tracing over a single piece of printed semilog paper. Oxoid Division). An internally illuminated box containing two strip lights that provide side illumination for the measurement of zones of inhibition (or exhibition) in the microbiological assay of antibiotics (or vitamins) using large 12-inch x 12-inch assay plates.Electrophoresis apparatus-T. H. Nelson (0x0 Ltd., Oxoid Division). A simple apparatus for use with cellulose acetate strips for rapid electrophoretic separation of proteins. An inexpensive incubator-T. H. Nelson (0x0 Ltd., Oxoid Division). A simple inexpensive incubator that has been shown to give remarkably constant temperature control. analysis-D. V. Carter (Standards Department, Boots Pure Drug Co. Ltd.). The diffusion plate-assay technique applied to enzymes and antibacterials in pharmaceutical Examples of the adaptation of the method to substances other than antibiotics and vitamins. JOINT MEETING A JOINT Meeting of the Society with the Oil and Colour Chemists Association was held at 7 p.m. on Wednesday, April 12th, 1961, at the Wellcome Building, Euston Road, London, N.W.I.The Chair was taken jointly by the President of the Society, Dr. A. J. Amos, F.R.I.C., and the Chairman of the London Section of the Oil and Colour Chemists Association, Mr. J. A. L. Hawkey. The following papers were presented and discussed: “Some Problems in the Analysis of Surface Coating Materials,” by C. Whalley, 13.Sc., F.R.I.C. ; “The Examination of Mixed Solvents Obtained from Plastic Adhesi\.es, Lacquers and Surface Coating Preparations,” by J. Haslam, D.Sc., F.R.I.C., A. R. Jeffs and H. A. Willis, B.Sc. ; “The Identification and Estimation of Pigments in Pigmented Compositions by Reflectance Spectrophotometry,” by D. R. Duncan, Ph.D., B.Sc. ORDINARY MEETING AN Ordinary Meeting of the Society was held at 7 p.m. on Wednesday, May 3rd, 1961, in the Meeting Room of the Chemical Society, Burlington House, London, W.l.The Chair was taken by the President, Dr. A. J. Amos, F.R.I.C. The following papers were presented and discussed: “The Combustion of Organic Com- pounds by Ignition in Oxygen: the Determination of Carbon and Hydrogen,” by G. Ingram, A.R.I.C. ; “Use of Induction Heating in Carbon and Hydrogen Determinations,” by Mrs. D. E. Buttenvorth ; “The Determination of Citronellol in Admixture with Geraniol ; Further Studies of Formylation Reactions Using Gas - Liquid Chromatography,” by D. Holness, B.A. ; “The Detection of ‘Additional Elements’ in Plastic Materials by the Oxygen-flask Combustion Method,” by J. Haslam, D.Sc., F.R.I.C., J. EL Hamilton and D. C. M. Squirrell, B.Sc., F.R.I.C.NEW MEMBERS ORDINARY MEMBERS Geoffrey Robert Andrews, A.C.T. (Birm.), A.R.I.C. ; James Michael Bakes; Kenneth Bilson; Michael Rex Burgess, B.Sc.(Lond) ; Charles Edward Carpenter, A.R.I.C. ; Douglas Vaughan Carter, B.Sc.(Nott.) ; Patrick Hamilton Cashman, B.A. (T.C.D.) ; Forster Cuthbertson, B.Sc., Ph.D. (Dunelm.) ; Peter Trevor Davies, M.A., Ph.D.(Cantab.), A.1nst.P. ; Robert Ellerby, B.Sc.(Lond.) ; Joan Ann Philomena Gibson, M.Sc.(N.U.I.) ; Peter Gittins, B.Sc., Ph.D.(Birm.), A.R.I.C. ; Geoffrey Green, F.I.M.L.T. ; Arthur Frederick LeCore Holding, B.Sc., Ph.D.(Lond.), A.R.I.C. ; George Frederick Hooke, A.R.I.C., A.C.T.(Liv.) ; Jack Lacy, B.Sc. (Dunelm.) ; Charles Frederick Luft, A.F.Inst.Pet., A.R.I.C. ; Walter Roy Marris; Harry Marsland; Derek George Parsons; Jos6 M.Puigmarti-Codina; Robert Best Stirton; Francis Henry Strutt ; Williams Alfred Stuart.May, 19611 PROCEEDINGS JUNIOR MEMBERS Richard Martin Lee, B.Sc.(Aber.) ; Shirley Ann Lord. NORTH OF ENGLAND SECTION AND PHYSICAL METHODS GROUP A JOINT Meeting of the North of England Section and the Physical Methods Group was held at 2.15 p.m. on Saturday, March 25th, 1961, at the City Laboratories, Mount Pleasant, Liverpool, 3. The Chair was taken by the Chairman of the North of England Section, Mr. J. Markland, B.Sc., F.R.I.C. The subject of the meeting was “The Analysis of Intact Samples” and the following papers were presented and discussed: “X-ray Fluorescence in General Analysis,” by D. E. Bromley, B.Sc., A.1nst.P. ; “The Use of Radioactive Isotopes in Simple X-ray Fluorescent Analysis,” by C.E. Mellish, R.A., D.Phi1. ; “Analysis by Nuclear Magnetic Resonance Tech- niques,” by D. J. Ferrett, M.A., D.Phi1. (see summaries below). X-RAY FLUORESCENCE IN GENERAL ANALYSIS MR. D. E. BROMLEY said that X-ray fluorescence was widely applicable, gave good accuracy and was quick and non-destructive, but there were difficulties with light elements, there was only moderate sensitivity and apparatus tended to be expensive. Attention had concentrated on repetition analysis, but X-ray fluorescence could be useful in more general work. Focusing curved-crystal spectrometers having good resolution and requiring only a small specimen had been made at Admiralty Materials Laboratory. One of these was of very simple construction, requiring only hand tools and a drill to make.A typical application was in the analysis of artificial rubies for chromium. A satisfactory calibration had been made with mixtures of powdered oxides, and a limiting sensitivity of 40 p.p.m. had been obtained. In the measurement of plating thickness, by using radiation from either the grating or the underlying metal, an approximate calibration depending on known absorption coefficients was possible. THE USE OF RADIOACTIVE ISOTOPES IN SIMPLE X-RAY FLUORESCENT ANALYSIS DR. C. E. MELLISH said that for many applications of X-ray fluorescence spectro- scopy the full performance of the conventional spectrometer was not required. In these applications it was possible to substitute a small radioactive source (1 millicurie) for the X-ray tube, provided that the crystal spectrometer was also dispensed with and resolution of the fluorescent X-rays produced was performed in a proportion or scintilla- tion counter.He gave results of the application of this simple system to such problems as the measurement of metal-plate thickness and of solution strengths and also discussed the suitability of different isotope sources for different applications. ANALYSIS BY NUCLEAR MAGNETIC RESONANCE TECHNIQUES DR. D. J. FERRETT said that the phenomenon of nuclear magnetic resonance, in which responses could be obtained from nuclei that had spin, offered a technique for the analysis of intact samples of solids, liquids and gases. Equipment demands were rigorous, e.g., magnets with highly uniform fields and electronic circuits with low noise levels.The information obtained could be both qualitative and quantitative and could be used as an aid to the elucidation of the structure of complex organic molecules. SCOTTISH SECTION AN Ordinary Meeting of the Section was held a t 7.15 p.m. on Friday, March 24th, 1961, in the Royal College of Science and Technology, George Street, Glasgow, C . l . The Chair was taken by the Chairman of the Section, Mr. A. F. Williams, B.Sc., F.R.I.C. The following papers were presented and discussed: “The Titration of Weak Acids in Non-aqueous Solvents,’’ by G. R. Jamieson, B.Sc., F.R.I.C. ; “High Frequency End-point Detection in Non-aqueous Titrimetry,” by E. S. Lane, B.Sc., Ph.D., F.R.I.C.284 PROCEEDINGS [vol. 86 MIDLANDS SECTION THE sixth Annual General Meeting of the Section was held at 6.30 p.m.on Tuesday, March 14th, 1961, at ’Regent House, St. Philip’s Place, Birmingham, 3. The Chair was taken by the Chairman of the Section, Dr. S. H. Jenkins, ‘F.R.T.C., F.1nst.S.P. The following appoint- ments were made for the ensuing year :-Chailrwzan-Dr. H. C. Smith. Vice-Chuirmun- Mr. W. H. Stephenson. Hon. Secretary-Mr. G. W. Cherry, 48 George Frederick Road, Sutton Coldfield, Warwickshire. Hon. Assistant Secretary-Mr. R. Adkins. Members of Committee-Mr. J. B. Aldred, Mr. B. E. Balfour, Professor R. Belcher, Dr. Bella B. Bauminger, Mr. H. J. G. Challis, Mr. W. T. Elwell, Miss C. J. Lloyd and Mr. A. Turner. Miss M. E. Tunnicliffe and Mr. J. Blenkin were re- appointed as Hon. Auditors. At the conclusion of the business of the Annual General Meeting, Dr.H. Weisz gave a short talk on “Advances in the Use of the Ring-oven Technique.” AN Ordinary Meeting of the Section was held a t 7 p.m. on Thursday, March 23rd, 1961, a t the College of Technology, Burton Street, Nottingham. The Chair was taken by Dr. S. H. Jenkins, F.R.I.C., F.Inst.S.P., Past Chairman of the Section. The following paper was presented and discussed : “The Measurement of pH and Electrode Potential for Analytical Purposes,’’ by G. Mattock, B.Sc., Ph.D., A.R.I.C. (see summary below). Hon. Treasuver-Mr. F. C. J. Poulton. THE MEASUREMENT OF pH AND ELECTRODE POTENTIAL FOR ANALYTICAL PURPOSES DR. G. MATTOCK said that the principal applications of potentiometric measurements in analytical chemistry were in pH determinations and various types of titration.How- ever, some recent developments in ion-selective electrodes showed promise in extending these fields. p H measurement- A pH determination was often an important parameter in many routine analytical procedures and might also be involved as a subsidiary control in analyses. Certain theoretical limitations existed, which, in general, precluded the significant determination of pH to better than 0.01 to 0.02 unit, particularly in media that could have widely varying compositions ; the theoretical uncertainty might be even greater with only partially aqueous systems, where pH measurements could only be comparative. These uncertainties derived from the conventional. nature of pH definitions and from variations in liquid-junction potentials.The conditions in which more discriminating measurements could be made were often too limiting for general analytical application. Experimental criteria involved a consideration of possible temperature errors, the general behaviour and pH ranges of glass electrodes and the reproducibilities of liquid- junction devices. To take examples: at low and high pH values experimental repro- ducibility of a high order might be difficult to achieve; and pH - temperature coefficients of alkaline solutions might be sufficiently large to cause confusion unless allowed for. Apparatus now available included highly discriminating pH meters of considerable stability. Single units incorporating botlh reference and glass-electrode components were available, permitting measurements on volumes of 1 to 2 ml, while for micro- volumes electrode systems requiring only 160 to 80 pl were also available.Potentiometric titration- Apart from the common glass-electrode pH titrations, redox titrations were frequently performed with platinum or gold redox electrodes and a reference electrode, which might be a conventional calomel, or a glass electrode, or tungsten. Noble metals followed redox equilibria by providing electrons in the redox exchange and adopted a potential, E, corresponding to the redox activity ratio- The chief difficulty in redox-electrode titrations occurred when electrode sluggishness appeared. The causes of this were not always clear, but could sometimes be relatedMay, 19611 PROCEEDINGS 285 to the formation of oxide films on the “noble” metal surface, and possibly also to the redox system not being thermodynamically reversible. Examples where sluggishness might occur, for example, were in Fe2+ - Cr20,2- and Fe2+ - V02+ titrations; in others, such as Fe2+ - Ce4+, no problems arose. In non-aqueous acid - base titrations, glass electrodes found considerable applica- tion, together with suitable non-aqueous reference electrodes, particularly in protogenic (acidic) and amphiprotic media.In protophilic (basic) media, platinum or antimony electrodes were usually preferable as indicators. An interesting new system was a mercury - Hg (EDTA) combination, which acted as an indicator electrode in potentiometric EDTA titrations. By suitable choice of pH conditions, groups of metals could be selectively titrated. One particularly useful example was in water hardness determinations, carried out at pH 8 to 10, where levels as low as 1 to 2 p.p.m. could be satisfactorily determined by the use of an amalgamated gold electrode and a calomel reference electrode, with addition of the mercuric salt of EDTA. Cation-responsive glass electrodes- A recent development in glass electrodes had been the introduction of stable glasses that were highly selective to singly charged cations, such as Na+. Sodium electrodes, for example, gave, analogously to pH, a “pNa” value and permitted direct measurement of sodium levels in solutions. The measuring range covered approximately molar to 10-6 molar (0.2 p.p.m. Na+), and could even be extended to 10-6 molar or weaker with certain controls. Their most obvious application was in continuous monitoring of sodium levels in water supplies, but they had been applied to determinations of saline content in processed fluids, such as yeast mixes. As a subsidiary item of possible analytical interest, it should be noted that sensitivity to univalent ions, such as silver and thallium1, had also been observed. MICROCHEMISTRY GROUP THE twenty-ninth London Discussion Meeting of the Group was held at 6.30 p.m. on Wednes- day, March 22nd, 1961, at “The Feathers,” Tudor Street, London, E.C.4. The Chair was taken by the Chairman of the Group, Mr. C. Whalley, B.Sc., F.R.I.C. A discussion on “The Separation and Determination of Traces of Iron” was opened by D. M. Peake and E. J. Newman, B.Sc., A.R.I.C. BIOLOGICAL METHODS GROUP A DISCUSSION Meeting of the Group was held at 6.30 p,m. on Thursday, April 6th, 1961, in “The Feathers,” Tudor Street, London, E.C.4. The Chair was taken by the Chairman of the Group, Mr. J. S. Simpson, F.I.M.L.T. A discussion on “Principles Involved in Collaborative Studies” was opened by S. A. Price, B.Sc., F.R.I.C.

ISSN:0003-2654    

DOI:10.1039/AN9618600277

出版商:RSC    

年代:1961

数据来源: RSC

摘要:

286 ANNUAL REPORT OF COUNCIL: MARCH, 1961 [Vol. 86 Annual Report of the Council: March, 1961 IT has become customary in the Annual Repclrts of Council presented in recent years to record the increasing and widening activities of the Society. The work of the Programmes Committee has been particularly important, and with it the planned provision of meetings that attempt to cover the whole field of modern analytical methods. It has also been a pleasure in previous years to record successful meetings organised by the Society in con- junction with Groups and Sections. Even judged against such a background, 1960 has been a particularly full and varied year. As an innovation this year, the Society’s Annual General Meeting and the Bernard Dyer Memorial Lecture were held, at the invitation of the Midlands Section, in Birmingham.This was the first occasion on which the Bernard Dyer Memorial Lecture had been given outside London, and Professor A. C. Frazer gave an address entitled “The Contribution of Analytical Chemistry to Medical Progress.” The lecture was followed in the evening by the Society’s Annual Dinner at which members of the Midlands Section and members from other parts of the country attended in almost equal numbers. The success of this function may well encourage the Society to plan future Annual General Meetings in centres other than London. During the year there have been some outstanding Joint Meetings with other Societies to whom analysis is an important and vital matter. In April, for example, a joint Symposium with the Fertiliser Society on the subject of “Fertiliser Analysis,” lasting 2 days, was held in Church House, Westminster; almost 200 people attended, of whom 20 were from overseas.In May, a 2-day Symposium was organised jointly with the Iron and Steel Institute and the Institute of Metals, in London. The subject was “The Determination of Gases in Metals”; more than 300 people attended, and it was particularly gratifying to have papers presented by leading workers from the United States. There was also a large attendance from European countries. The Proceedings of the Symposium have now been published in book form by the Iron and Steel Institute. Another important event in which the Society played a prominent part was the Third Gas Chromatography Symposium held in Edinburgh in June. This was organised jointly by the Society and the Gas Chromatography Dixussion Group of the Hydrocarbon Research Group of the Institute of Petroleum.The meeting extended over 4 days and was held in the Assembly Rooms, George Street, Edinburgh. There were more than 560 delegates, including 160 from overseas, and a large number of applications had to be refused. The Organising Committee, of which Mr. L. Brealey was Secretary, was nobly supported in Edinburgh by the Scottish Section, who undertook a great many of the local arrangements. In July he presented an Address on behalf of the Societ to the Royal Society on the occasion of its among other learned bodies. In September, a t the invitation of the Chemical Societies of Sweden and Denmark, he made a lecture tour, during which he conveyed greetings from the Council to those Societies.The Ramsay Chemical Dinner, in December of this year, was the first occasion at which the President of the Society for Analytical Chemistry was Chairman. Mr. Chirnside also gave the Ramsay Lecture, entitled “ Ramsay, Chemistry and the Electrical Industry.” Activities of the Sections and Groups have again been widespread, joint meetings with other bodies forming an increasing proportion of the total meetings. Of particular interest were the 2-day Symposium on “Analytical Che:mistry in the Service of Agriculture” held in Nottingham in July, and the joint meeting of the Scottish Section with the Polarographic Society and the Caithness Technical Society at Dounreay in September.The Analytical Methods Committee has again extended its activities, and during the year the work of its many committees has progressed. Methods of analysis for additives in animal feeding stuffs-work being undertaken a t the request of the Scientific Sub-committee of the Ministry of Agriculture, Fisheries and Food-hats reached an advanced stage and publication can be expected in the near future. A research scholar has been appointed to work at Rotham- sted Experimental Station on the investigation of bioassay methods for determining toxic The year 1960 has also been eventful for the President, Mr. R. C. Chirnside. Tercentenary-the invitation from the Royal l cciety acknowledging the status of the SocietyMay, 19611 ANNUAL REPORT OF COUNCIL: MARCH, 1961 287 pesticide residues in foodstuffs, this appointment following on the report by Mr.P. H. Needham on the use of such methods, published in The Analyst. The Annual Conference of Honorary Secretaries of Sections and Groups was held on May 17th, 1960. Once again the meeting proved of great value to the Honorary Secretaries in enabling them to meet and discuss questions of mutual interest. The advisability of altering the date of the Conference was discussed so that it might be easier for joint meetings to be planned. Council records with pleasure the award of the C.B.E. to Mr. E. J. Vaughan, the award of the O.B.E. to Mr. M. Lovett and Mr. A. A. Smales and the award of the M.B.E. to Mr. C. H. Allen. The Society now has 1998 members, an increase of 57 over the membership of a year ago.LONG MEMBERSHIP-The congratulations and good wishes of the Council are extended to Sir Harry Jephcott and Mr. P. N. Mould, who have completed 40 years of membership. DEATHS-The Council regrets to have to record the deaths of the following members- F. W. F. Arnaud A. Lees W. B. Shaw A. Bacon H. Lowe W. H. Simmons H. Baggesgaard-Rasmussen W. Marsden L. H. Smith E. Brodaty J. McCrae G. Taylor A. S. Carlos J. H. Oliver G. Thomas R. D. T. E. Chandler J. W. Paterson T. Tickle E. M. Hawkins P. Schidrowitz R. F. Wright L. G. S. Hebbs SOCIETY MEETINGS-Ten meetings of the Society were held during the year and the following papers were read and discussed- March, 1960, in London, Joint Meeting with the Fine Chemicals Group of the Society of Chemical Industry on Techniques of Automatic Analysis : “Automatic Analysis in the Chemical Industry,” by R.M. Pearson, A.R.I.C. “Automation in Clinical Biochemistry,” by I. D. P. Wootton, M.A., M.B., Ph.D., F.R.I.C. April, 1960, in London: “A Combined Gravimetric and Photometric Procedure for the Determination of Silica in Silicate Rocks and Minerals,” by P. G. Jeffery, M.Sc., Ph.D., D.I.C., A.R.C.S., F.R.I.C., and A. D. Wilson, B.Sc. “The Estimation of Trimethylene Glycol in Glycerol by Gas Chromatography,” by J. Clifford, B.Sc., M.A. “Direct Colorimetric Determination of Trace Chloride,” by T. Nash, M.A., B.Sc., A.R.I.C. April, 1960, in London, Joint Symposium with the Fertiliser Society on Fertiliser Analysis: Nine papers were read a t this meeting; for details see The Analyst, 1960,85, 305.May, 1960, in London, Joint Symposium with the Iron and Steel Institute and the Institute of Metals on The Determination of Gases in Metals: Sixteen papers were read a t this meeting: for details see The Analyst, 1960, 85, 385. June, 1960, in Edinburgh, Joint Symposium with the Gas Chromatography Discussion Group of the Hydrocarbon Research Group of the Institute of Petroleum : Thirty-five papers were read a t this meeting. A report of -the Symposium appears in The Analyst, 1960, 85, 457. September, 1960, in London, on The Chemist and Food Quality: “The Food Analyst To-day and Yesterday,” by A. J. Amos, B.Sc., Ph.D., F.R.I.C. “Some Applications of Research to the Study and Control of Consistency in Certain Foods,” by E. H. Steiner, B.Sc., F.R.I.C.“Estimation of the Polyphenolic Oxidation Products in Tea as an Assessment of Tea Quality- The Spectrophotometric Estimation of Theaflavins and Thearubigins in Black Tea Liquors,” by E. A. H. Roberts, M.A., D.Phil., and R. F. Smith, B.Sc., F.R.I.C. “The Analysis of Volatile Strawberry Flavours,” by D. S. Bidmead, A.R.I.C.288 ANNUAL REPORT OF COUNCIL: MARCH, 1961 [Vol. 86 October, 1960, in London: “Paper Chromatography of Some Organo-tin Compounds,” by D. J . Williams, B.Sc., and J. W. “A Procedure for Determining the Molar Extinction Coefficients of Metal Dithizonates,” by “The Spectrophotometric Determination of Microgram Amounts of Calcium,” by J . R. W. Kerr. Price, Ph.D., F.R.I.C. H. M. N. H. Irving, M.A., D.Phil., D,Sc., F.R.I.C., and R. S. Ramakrishna, B.Sc.November, 1960, in London, on Analysis of Semi-conductors : Introductory Remarks by C. A. Parker, B.Sc., I’h.D., F.R.I.C. “The Determination of Some Trace Impurities in Gallium Arsenide by Square-wave Polarography,” “The Determination of Phosphorus in Silicon by a Fluorimetric Method,” by R. E. Minns, A.R.I.C. “Experiments on the Detection and Determination of Impurities in Silicon by Means of Gas Chrom- “The Determination of Boron in Silicon by Isotope Dilution,” by D. C. Newton, B.Sc., J. Sanders, “The Spectrographic Analysis of Trace Impurities in Indium, following Chemical Concentration,” “Determination of Impurities in Semi-conductors by Spark-source Mass Spectrometry,” by R. “Radioactivation Analysis, by V. J.. Jennings, B.Sc., Ph.D. atography,” by J.E. Still, B.Sc., F.R.I.C., and R. C. Chirnside, F.R.I.C. A.I.M., and A. C. Tyrrell. by J. F. Duke, B.A., H. R. Whitehead, B.Sc., and H. R. Sullivan. Brown and J. D. Waldl;pn, B.Sc., Ph.D. by J. A. James, M.A., B.Sc., A.R.I.C. December, 1960, in London, on The Flask Combustion Technique : Introduction by W. Schoniger, Dr.ing. “Apparatus for Electrical Ignition,” by J. Haslam, D.Sc., F.R.I.C., J. B. Hamilton and D. C. M. “Determination of Halogens,” by C. A. Johnson, B.Pharm., B.Sc., F.P.S., F.R.I.C. “Determination of Boron,” by Miss M. Corner, :B.Sc., F.R.I.C. “Determination of Phosphorus,” by E. Q. Laws, B.Sc., F.R.I.C. “Determination of Sulphur,’’ by Miss J. P. Dixon, A.R.I.C. Squirrell, B.Sc., F.R.I.C. February, 1961 , in London, on X-ray Fluorescence, organised by the Physical Methods Group : “X-ray Fluorescence Spectroscopy, ” by K. M.Bills. “Some Analytical Applications of X-ray Fluorescence Spectrometry,” by F. Brown, B.Sc., Ph.D., A.R.I.C. NORTH OF ENGLAND SECTION-The membership of the Section is 430, compared with 411 last year. During 1960, ten meetings were held, including four Joint Meetings and the usual Summer Meeting. The following papers were read and discussed- Manchester, January, 1960, Annual General Meeting : Manchester, March, 1960: Liverpool, April, 1960: Hull, May, 1960, jointly with the Microchemistry Group and the University of Hull Chemical “Analytical Methods in Clinical Biochemistry,” by H. Varley, M.Sc., F.R.I.C. “The Analysis of Non-soapy Detergent Product!;,” by G. F. Longman, B.Sc., F.R.I.C.“The Application of Isotopes to Analysis,” by G. B. Cook, Ph.D., and J. W. Lucas, BSc., F.R.I.C. Society, on Corrosion: “Oxidation of Metals by Oxygen a t High Temperatures,” by S. J . Gregg, DSc., F.R.I.C., A.R.C.S. “X-ray Studies of Some Metal Oxidation and. Corrosion Problems,” by H. P. Rooksby, B.Sc., F.1nst.P. Llandudno, June, 1960, Summer Meeting: Chester, September, 1960, jointly with the Physical Methods Group : “The Baking Scientist,” by J. B. M. Coppock, O.B.E., Ph.D., F.R.I.C. “Applications of X-ray Spectrometry in the Oil Industry,” by R. W. Toft, A.R.I.C., D.I.C. “The Identification of Substances of Low Volatility by Pyrolysis - Gas Liquid Chromatography,” by G. C. Hewitt, B.Sc., Ph.D., and B. T. Whitham, B.Sc., A.R.I.C. Bangor, September, 1960, jointly with the “icrochemistry Group and the North Wales “Techniques and Scales of Analysis,” by Professor R.Belcher, Ph.D., DSc., F.R.I.C., F.Inst.F., Section of the Royal Institute of Chemistry : and Professor C. L. Wilson, Ph.D., D.Sc., F.R.I.C., F.I.C.I.May, 19611 ANNUAL REPORT OF COUNCIL: MARCH, 1961 Leeds, November, 1960: “The Analytical Chemistry of Phosphorus,” by N. T. Wilkinson, F.R.I.C. 289 Newcastle, November, 1960, jointly with the Newcastle and North-East Coast Section of the Royal Institute of Chemistry: “The Changing Aspect of Chemical Analysis,” by H. N. Wilson, F.R.I.C. Liverpool, December, 1960: “Experiences in the Estimation of Some Elements in. Foodstuffs,” by H. Pritchard, M.Sc., F.R.I.C. SCOTTISH SECTION-The membership of the Section has decreased by 11 to 116.The Section has had a particularly active year, despite one scientific meeting less than in 1959; of the meetings held, four were in Glasgow, two in Edinburgh, and the seventh took the form of a Joint Meeting with the Polarographic Society and the Caithness Technical Society, held at Dounreay in the Lecture Hall of the Experimental Reactor Establishment of the U.K.A.E.A. After the papers and afternoon tea, the visitors were taken on a most interesting tour of the Establishment, which included the Fast Reactor and the Analytical Laboratories. Of the Glasgow meetings, the first was the twenty-fifth Annual General Meeting, which took the usual form of a lunch, followed by the business meeting and an address from our Past President, Dr.D. W. Kent-Jones. The last meeting in Glasgow was of particular significance, not only as the annual occasion when the Society now combines with the three Chartered Bodies as joint sponsor, but in that responsibility for arranging the meeting fell this year on the Society. The Section was very fortunate in being able to call on our President, who was in Glasgow from the previous evening, where he had most successfully Chaired the 1960 Ramsay Dinner, at which the Principal Guest was Sir Alexander Fleck. Last, but certainly not least, the major activity of the Section during the first half of the year was in the organisation of many aspects of the Third Gas Chromatography Symposium, jointly with the Gas Chromatography Discussion Group of the Hydrocarbon Research Group of the Institute of Petroleum, and our Society, culminating in the highly successful holding of the Symposium in the Assembly Rooms, Edinburgh, during the second week of June.The following papers have been presented and discussed- Edinburgh, January, 1960 : “Applications of Infra-red Spectroscopy,’’ by L. J. Bellamy, B.%. , Ph.D. “An Application of G.L.C.-Infra-red Spectroscopy Technique,” by D. M. W. Anderson, B.Sc., Ph.D., A.R.I.C. Glasgow, January, 1960, Annual General Meeting : “The Work of the Cereal Chemist: Some Aspects of New Techniques,” by D. W. Kent-Jones, B.Sc., Ph.D., F.R.I.C. Glasgow, February, 1960 : “Analytical Methods in the Hygienic Control of Industrial Atmospheres,” by J. C. Gage, B.Sc., “Analytical Problems in the Isolation and Measurement of Traces of Radioactivity in Foods,” by Ph.D., F.R.I.C.Professor J. Hawthorn, B.Sc., Ph.D., A.R.C.S.T., F.R.I.C. Edinburgh, March, 1960: “The Control of Quality in Synthetic Foodstuff Colours,” by H. E. Stagg, B.Sc., F.R.I.C. Glasgow, April, 1960 : “Chemical Services on British Railways,” by G. H. Wyatt, B.Sc., Ph.D., F.R.I.C. Dounreay, September, 1960, jointly with the Polarographic Society and the Caithness Tech- nical Society: “Tesla-luminescence in Inorganic and Organic Systems,” by R. J. Magee, M.Sc., Ph.D., A.R.I.C. “Applications of Polarography in Industrial Analysis,” by G. F. Reynolds, M.Sc. , F.R.I.C. “The Assay of Carbon-14 and Other Low-energy p-emitters,” by J. C. Bevington, M.A., Ph.D., D.Sc.290 ANNUAL REPORT OF COUNCIL: MARCH, 1961 [Vol.86 Edinburgh, October, 1960 : “Some Aspects of the Analytical Chemistry of the Heteropolymolybdates,” by R. A. Chalmers, “A Colorimetric Determination of Sulphite,” by W. Moser, BSc., R. A. Chalmers, B.Sc., Ph.D., “Some Factors Affecting the Use of Amalgams a s Reductants,” by R. A. Chalmers, B.Sc., Ph.D., Glasgow, December, 1960, jointly with the Chemical Society, the Society of Chemical Industry B.Sc., Ph.D., and A. G. Sinclajr, BSc. and A. G. Fogg. W. Moser, B.Sc., and D. A. Thomson, BSc. and the Royal Institute of Chemistry: “Ramsay, Chemistry and the Electrical Industry,” by R. C. Chirnside, F.R.I.C. WESTERN SECTION-The membership of the Section is 102, an increase of 1 during the year. Since the beginning of 1960, 6 meetings have been held, including the A.G.M.All have been joint meetings with the Royal Institute of Clt~mistry or the Society of Chemical Industry, or both, or with other sections of our ~ w n Society. As in previous years, the meetings have been widely separated over the area of the Section and attendances have been good, except for isolated instances when the meeting has clashed with other meetings in the area. The following papers have been presented and discussed- Chemistry : January, 1960, Bristol, jointly with the Bristol and District Section of the Royal Institute of “Radiochemical Analysis,” by J. N. Andrews, ELSc., Ph.D., D.I.C., A.R.I.C. March, 1960, Swansea, jointly with the South Wales Section of the Royal Institute of Chemistry : “Advantages and Disadvantages of Visual Colorimetry,” by G.J. Chamberlin. May, 1960, Poole, jointly with the Physical Methods Group, on Atomic-absorption Spectra- “Some Factors Affecting Performance in Atomic Absorption Spectroscopy,” by R. Lockyer, B.sc. , “The Flame as a Source of Atoms,” by C. A. Baker, M.A., D.Phi1. “The Application of Atomic-absorption Spectrophotometry to Metallurgical Analysis,” by w. T. May, 1960, Plymouth, Summer meeting jointly with the South Western Counties Section of scopy : F.R.I.C. Elwell, F.R.I.C., and J. A. F. Gidley, BSc., A.1nst.P. the Royal Institute of Chemistry: “Trace Elements in Sea-water,” by L. H. N. Cooper, Ph.D., DSc. October, 1960, Salisbury, jointly with the Mid-Southern Counties Section of the Royal Institute of Chemistry : ‘‘Some Observations on Analytical Chemistry, ” by J.Haslam, D.Sc. , F.R.I.C. December, 1960, Newport, jointly with the Cardiff and District Section of the Royal Institute of Chemistry and the South Wales Section of the Society of Chemical Industry: “Radioactivity in Relation to Water Supplies,” by F. P. Hornby, B.Sc., F.R.I.C. MIDLANDS SEcTIoN-The membership of the Section on December 31st, 1960, was 344, consisting of 310 ordinary members and 34 junior members. This is an increase of 8 ordinary members and 1 junior member during the year. The programme for 1960 has been marked by three events of outstanding interest. Continuing the practice of the.Secti?n to invite every year an eminent chemist from abroad to speak on some topic of direct Interest to analytical chemists, Professor Gutmann of Vienna gave a stimulating talk on “Some AIlalytical Aspects of Reactions in Non-aqueous Solutions.” This meeting was held on Febr1m-y 24th jointly with the Birmingham and Midlands Section of the Royal Institute of Chemistry.In July the Section organised a successful 2-day Symposium on “Analytical Chemistry in the Service of Agriculture.’ Held in one of the Halls of Residence of Nottinghalm University, this venture attracted upwards of 80 delegates, including a number of visitors from the Continent. Mr. R. C. Chirnside, President of the Society, made the opening adtlress, and in the subsequent sessions the Chair There are 9 Honorary Members.May, 19611 ANNUAL REPORT O F COUNCIL: MARCH, 1961 29 1 was taken by Dr. D. C. Garratt, Professor R. Belcher and Dr. S. H. Jenkins.During the Symposium, visits were paid to the Veterinary and Horticultural Research Stations of Messrs. Boots Pure Drug Co. , and an informal dinner was held in the Portland Building of the Univer- sity. Three of the papers submitted in the competition for the Elwell Award were read at a meeting of the Section in September, 1960. The Award consists of a silver cigarette box having an inlaid plaque in some of the newer industrial metals and is held for 1 year by a chemist not over 30 years of age who, in the opinion of a panel of judges, submits the best paper on an analytical topic. A gift of books to the value of 3 guineas accompanies the Trophy, which on this occasion was awarded to Mr. D. J. Brindley for a paper on “The Polaro- graphic Determination of Niobium in Highly Alloyed Steels.” The following papers have been presented and discussed- Seven papers were read and summaries appear in The Autalyst, 1960, 85, 617.January, 1960, Birmingham: presentation of papers for the Elwell Award, 1959: “The Polarographic Determination of Small Amounts of Tin and Lead in Zirconium and its Alloys,” “Neutron Activation Analysis of High Purity Aluminium,” by D. Hazelby. “The Assay of Sodium Citrate and Sodium Potassium Tartrate by (a) Cation Exchange and (b) Non- by R. T. Clark. Aqueous Titrimetry,” by M. L. Richardson. January, 1960, Birmingham, jointly with the Microchemistry Group : February, 1960, Birmingham, jointly with the Birmingham and Midlands Section of the “Micro Gas Analysis,” by G. J. Minkoff, DSc., D.I.C. Royal Institute of Chemistry : “Some Analytical Aspects of Reactions in Certain Non-aqueous Solutions,” by Professor V.Gutmann. March, 1960, Birmingham : “Plant Growth Promoting Substances-Some Analytical Aspects,” by Professor R. L. Wain, D.Sc. , Ph.D., F.R.I.C. March, 1960, Nottingham : April, 1960, Birmingham : Annual General Meeting. “The Analytical Chemistry of Titanium and Zirconium,” by W. T. Elwell, F.R.I.C., and D. F. Wood, BSc., A.R.I.C. May, 1960, Nottingham : “The Application of Gas - Liquid Chromatography to the Analysis of Essential Oils,” by D. Holness, B.A. July, 1960, Nottingham, Symposium on Analytical Chemistry in the Service of Agriculture : September, 1960, Birmingham: presentation of papers for the Elwell Award, 1960: Seven papers were read a t this meeting; for details see The Analyst, 1960,85, 617.“The Polarographic Determination of Niobium in Highly Alloyed Steels,” by D. J. Brindley. “The Identification of Vapour-phase and Liquid-phase Gums Found in Gas Plant and Appliances,” “Moisture Determination in Carbon Dioxide Gas”, by J. A. Roff. by P. M. Owens. October, 1960, Coventry: October, 1960, Nottingham: November, 1960, Birmingham, jointly with the Birmingham and Midlands Section of the “The Analytical Chemistry of Chromium and Vanadium,” by G. M. Holmes, F.R.I.C. “Paper Chromatography of Dyestuffs,” by J. C. Brown. Royal Institute of Chemistry: “Analytical Problems in Forensic Toxicology,” by F. L. Cann, B.Sc. , A.R.I.C. December, 1960, Birmingham : “The Analysis of Waters Used in Industry,” by K. B. Coates.292 ANNUAL REPORT OF COUPJCIL: MARCH, 1961 December, 1960, Nottingham : “The Development of the Analytical Balance,” by K.M. Ogden. [Vol. 86 MICROCHEMISTRY GROUP-The membership of the Group is now 718, an increase of 29 in the past year. During 1960 four Ordinary Meetings of the Group were held: in Birmingham on January 12th (together with the Midlands Section) ; in London on February 19th (the Annual General Meeting of the Group followed by a Joint Meeting with the Biological Methods Group); in Hull on May 13th (jointly with the North of England Section and the University of Hull Chemical Society) ; and in Bangor on September 30th and October 1st (together with the North of England Section and the North Wales Section of the Royal Institute of Chemistry).The following papers were read- Birmingham : London : Details of the paper read a t this meeting are given in the report on the Midlands Section. “Micro-analysis in Clinical Biochemistry,” by Professor E. J. King, M.A., D.Sc., F.R.I.C. “Completely Automatic Methods in Micro-analysis,” by I. D. P. Wootton, M.A., M.B., Ph.D., “Automatic Titration Apparatus,” by Ruth Haslam, M.B., D.C.P., and I. D. P. Wootton, M.A., “Flame Photometric Analysis of Divalent Cati0n.s in Biological Materials,’’ by I. MacIntyre, M.B. “Optical Rotatory Dispersion,” by W. Klyne, M.A., D.Sc. “Spectrofluorimetric Determination of Alkaline Phosphatase in Micro Quantities of Serum,” by F.R.I.C. M.B., Ph.D., F.R.I.C. D. W. Moss, M.A. Hull : Details of the papers read a t this meeting are given in the report on the North of England Section. Bangor : Details of the paper read a t this meeting are givein in the report on the North of England Section.Five informal discussion meetings were held in London and one in Bangor. The following “Treatment of Inorganic and Organic Materials for the Determination of Metals,” introduced by “Titrations in Non-aqueous Solvents,” introduced by E. H. Tinley, B.Sc., F.P.S. “The Direct Determination of Oxygen,” introduced by D. W. Wilson, M.Sc., F.R.I.C. “Techniques and Scales of Analysis,” introduced by Professor R. Belcher, Ph.D., D.Sc., F.R.I.C., “Analytical Aspects of Corrosion,” introduced by H. C. J. Saint, A.R.I.C. A Review of Topics in Organic Micro-analysis. are the topics discussed, and the speakers who introduced them- C.Whalley, B.Sc., F.R.I.C. F.Inst.F., and Professor C. L. Wilson, Ph.D., D.Sc., F.R.I.C., F.I.C.I. PHYSICAL METHODS GROUP-The membership of the Group is now 782, an increase of 32 since the last Annual Report. During the past year the Group has held four Ordinary Meetings and organised a Joint Meeting of the Society with the Oils and Fats Group of the Society of Chemical Industry in February. Two of the Ordinary Meetings were held in London and one each in Poole, Chester and Oxford. The Poole meeting was held jointly with the Western Section, the Chester meeting with the North of England Section and the Oxford meeting with the Thames Valley Section of the Royal Institute of Chemistry. Following the Annual General Meeting on November 24th, 1959, the retiring Chairman, Mr.R. A. C. Isbell, delivered a lecture entitled “The Design of Optical Instruments for Chemical Analysis.” The following papers were read and discussed a t the Ordinary Meetings of the Group- Automatic Analytical Instrumentation-London, April, 1960 : “Auto Analyzer,” by A. L. J. Buckle, M.Sc., Ph.D., A.R.I.C. “E.I.L. Model 24 Automatic Titrimeter,” by G. Mattock, B.Sc., Ph.D., A.R.I.C. “D. C. L. Null-balance Magnetic Oxygen Analyser,” by C. W. Munday, B.Sc., A.R.I.C. “Mervyn - CERL Automatic Sulphur Dioxide Recorder,” by Mrs. M. W. Redfearn.May, 19611 ANNUAL REPORT OF COUNCIL: MARCH, 1961 293 Atomic-absorption Spectroscopy-Poole, May, 1960 : Chester, September, 1960: Nuclear Magnetic Resonance-Oxford, October, 1960: Details of the papers read a t this meeting are given in the report on the Western Section. Details of the papers read at this meeting are given in the report on the North of England Section.General Introduction by R. E. Richards, M.A., D.Phil., F.R.S. “The Application of Broad-line Nuclear Magnetic Resonance to Inorganic Analysis,” by D. J . “Applications of Nuclear Magnetic Resonance in Organic Chemistry,” by L. M. Jackman, Ph.D. Ferrett, M.A., D.Phil. BIOLOGICAL METHODS GROUP-During the year the membership of the Group has de- In the year ending October 31st, 1960, the Group has held, in addition to the Annual The following creased from 310 to 308. General Meeting, five Ordinary Meetings and made one laboratory visit. papers were read and discussed- December, 1959, London, on Biological Methods in Forensic Science: “Biological Methods in Forensic Toxicology,” by A.S. Curry, M.A., Ph.D., A.R.I.C. “Some Experiments on the Determination of Alcohol in Biological Fluids by the Alcohol Dehydro- “Enzymes and Antibodies in Forensic Science,” by S. S. Kind, B.Sc. genase Method,” by H. J. Walls, B.Sc., Ph.D. January, 1960, London : February, 1960, London, jointly with the Microchemistry Group : April, 1960, London, on Hormones in Clinical Practice : “Antibiotic Assays in Body Fluids,” by Professor L. Garrod, M.A., M.D., F.R.C.P. DetaiIs of the papers read a t this meeting are given in the report on the Microchemistry Group. “Assay of Gonadotrophins in Body Fluids,” by J. A. Loraine, M.D., Ch.B., M.R.C.P. “Insulin Assay in Plasma by the Rat Diaphragm Method,” by P.H. Wright, M.Sc., M.B., Ch.B. October, 1960, London, on The Biological Assay of Insecticidal Residues : Introduction by J. H. Hamence, MSc., Ph.D., F.R.I.C. “Biological Techniques for the Detection and Estimation of Insecticidal Residues,” by P. H. Need “Industrial Approach to the Biological Assay of Insecticidal Residues,” J. G. Reynolds, F.R.I.C., ham, B.Sc. and R. Goulden, F.R.I.C. ANALYTICAL METHODS COMMITTEE-During the past year the Committee, its Sub- Committees and Panels, and the Joint Committee with The Pharmaceutical Society, have maintained the level of activity reported a year ago. Three new Committees have been appointed and one Panel of the joint Committee has been disbanded on completion of its work: the total number of Committees is now 22, an increase of 2 over last year.In addition to the Annual Report of the Committee, 6 Reports of Sub-committees and Panels and 2 Reports of special investigational work have been published in The Analyst. These are- Reports of Sub-Committees and Panels : “Fiore Method for Determining Linalol : Amendment,” by the Essential Oils Sub-committee (March). “The Determination of Small Amounts of Arsenic in Organic Matter,” by the Metallic Impurities “Methods for the Destruction of Organic Matter,” by the Metallic Impurities in Organic Matter “Assay of Rauwolfia,” by the Joint Committee of The Pharmaceutical Society and the Society for in Organic Matter Sub-committee (September). Sub-committee (September). Analytical Chemistry (October). Reports of Panels (set up jointly by the Scientific Sub-committee of the Interdepartmental Advisory Committee on Poisonous Substances Used in Agriculture and Food Storage, the Analytical Methods Committee of the Society and the Association of British Manufacturers of Agricultural Chemicals) : “The Determination of Small Amounts of DDT in Flour and Other Foodstuffs” (August).“The Determination of Malathion Residues in Cereals and Oilseeds” (December).294 ANNUAL REPORT OF COUI\TCIL: MARCH, 1961 [Vol. 86 Reports of Special Investigational Work : “The Determination of Trace Quantities of Silver in Trade Effluents,” by T. B. Pierce (March). “Investigation into the Use of Bioassay for Pesticide Residues in FoodstuffsJJJ by P. H. Needham (November). The investigational work published in the last-named Report formed the basis of an evening meeting organised by the Biological Metlhods Group in October.A further development arising from Mr. Needham’s investigations has been the appoint- ment of the Society’s second Scholar, Dr. J. H. Stevenson, to carry out research for a year at Rothamsted Experimental Station under Mk. Needham’s supervision. The research work is directed, in the first instance, to a comparison of the general sensitivities and con- venience in use of a limited number of organisms that are already known to be reactive to small amounts of toxic pesticides. The various Sub-committees and Panels of the Analytical Methods Committee have continued to be active throughout the year and special mention may be made of the progress made by the Additives in Animal Feeding Stuffs Sub-committee and its associated Sub- committee on Trace Elements in Fertilisers and Fleeding Stuffs.The latter Sub-committee is nearing the end of its programme and it is hoped to publish within the next year a full report of its work covering investigations into methods of analysis for 15 elements and giving details of the methods finally recommended. All the five Panels of the former Sub-committee have been very active during the year and a number of reports are in course of preparation; it is hoped that these will be published during the coming year. The Metallic Impurities in Organic Matter Sub-committee published two reports in the September issue of The Analyst, and work is now proceeding on methods for copper and mercury One new Sub-committee of the Analytical Methods Committee-that on primary ana- lytical standards-has been appointed, following a request from the Analytical Chemistry Section of I.U.P.A.C. for a critical examination of the various substances that have been proposed as standards, with a view to making specific recommendations on behalf of the United Kingdom.Two new Panels of the Joint Committee with The Pharmaceutical Society were appointed during the year-one to investigate methods of assay of pyrethrum and the other to investi- gate the biological methods of assay of anthraquinone drugs. After the publication of the report on the Assay of Rauwolfia, the Panel concerned with its preparation has been dis- banded. Two of the other Panels of the Joint Committee, whose first Reports were published in 1959, are continuing their work.Mr. S. C. Jolly, whose appointment as part-time Publications Secretary was announced a year ago, is engaged in revising the Bibliography of Standard, Tentative and Recommended or Recognised Methods of Analysis, originally published in 1951, and is also editing all the recommended methods that have been published from time to time in Reports of the Analytical Methods Committee with a view to their publicattion as a collection of the Society’s recom- mended methods of analysis. As in other years, a separate Report of the Analytical Methods Committee, giving full details of the work of all Sub-committees and Panels, is being prepared and will be circulated to all contributors to the Analytical Methods Trust Fund.ments were made- LIAISON WITH OTHER SCIENTIFIC ORGANISATIONs-During the year the following appoint- Joint Library Committee, Chemical Society : British Iron and Steel Research Association : Dr. J. G. A. Griffiths. Mr. R. C. Chirnside and Dr. J. Haslam represented the Society at the Fourteenth Chemists’ Conference of the Methods of Analysis Committee (Metallurgy, General, Division). Parliamentary and Scientific Committee: Royal Institute of Chemistry, Summer School Organising Committee : Dr. J. H. Hamence. Mr. A. N. Leather and Mr. C. Whalley.May, 19611 ANNUAL REPORT OF COUNCIL: MARCH, 1961 295 Chemical Council : Dr. A. J. Amos. B.S.I. Committees: Mr. S. A. Price: Chemical Divisional Council. Dr. R. A. Lawrie: Meat and Meat Products.Dr. J. H. Hamence: Cereals and Pulses. Dr. K. A. Williams: Oils, Seeds and Vegetable Oils. Mr. L. J. Hamilton : Antibiotics in Dairy Products. Dr. J. G. Davis: Sampling of Dairy Products. Mr. A. G. Hill: Lovibond Colour Scale-C.I.E. System. Dr. K. A. Williams: Home Produced Technical Tallow. Dr. K. A. Williams : Home Produced Technical Bonegrease. Standing Advisory Council, Fertilisers and Feeding Stuffs Act : Dr. J. H. Hamence. British National Committee for Chemistry: Dr. R. E. Stuckey. The Council of the Society thanks all its representatives for the work they have carried out in the various Committees and at varied meetings during the year. HONORARY TREASURER’S REPORT-The income derived from each of the sources from which the Society obtains most of its revenue, namely, members’ subscriptions, sales of The Analyst and Analytical Abstracts, advertisements and interest on investments, was greater in theyear ended October 31st, 1960, than in the previous year, the total increase in revenue from these sources being E3137, but the profit on “other publications” was less in 1960 by k425 because of the concentration of sales of the Decennial Index in 1959.The net result was a rise in income of E2712. On the expenditure side the cost of producing and distributing The Analyst and Analytical Abstracts rose by E3823, an increase greater than the total increase in income, and sums of L303 and L445 were spent respectively upon the publication of a new List of Members and upon redecoration of the Council Room. Hence, despite the enhanced revenue the surplus of income over expenditure excluding money put to ieserves was less than that of 1959 by 41557.0.. Despite this expected fall in the disposable surplus of income over expenditure, the sum available for distribution between reserves and the Accumulated Fund at the close of the Society’s books in 1960 was E6827, an outcome that fully justifies the confident outlook reported last year. The cost of administering the Society’s activities, excluding expenditure on publications, the finances of the Analytical Methods Committee and money put to reserves, represents a charge of &2 10s. Od. per member. For the remaining 13s. of his subscription each member receives each year copies of The AnaZyst and Analytical Abstracts. the annual subscription for which to non-members is -@ 8s.Od. PROGRAMMES COMMITTEE-The Committee arranged an ambitious series of meetings during 1960. A glance down the list given earlier in this report will indicate how an attempt was made to break away from the usual type of programme and also to cater for as wide a section of Society members as possible. The policy of establishing closer contacts with other learned Societies and Groups is indicated by the fact that out of ten meetings or Symposia arranged, four were held jointly with other bodies. As in previous years, two evening meetings were devoted to the presentation of papers submitted for publication in The Analyst. These attracted somewhat larger audiences than had attended previous meetings of this kind, but the attendances in general were still some- what disappointing.On the other hand the joint meeting with the Fine Chemicals Group of the Society of Chemical Industry on “Techniques of Automatic Analysis,” the meeting on “Analysis of Semiconductors” and that on “The Flask Combustion Technique” proved extremely popular.296 ANNUAL REPORT OF COUNCIL: MARCH, 1961 [Vol. 86 Special mention should be made of the three Symposia. The first one, held jointly with the Fertiliser Society on “Fertiliser Analysis,” provided a platform for the presentation of work done by Committees from both Societies, and rnany of the methods described during the meeting may well become standard in the Fertiliser Industry. The Symposium arranged jointly with the Iron and Steel Institute and the Institute of Metals was important, not only for the fact that it was the first time “The Determination of Gases in Metals” had been the subject of a Symposium in this country, but became it was the first time that the two Insti- tutes had come together for a meeting of any kind.The response so greatly exceeded the expectations of the Organising Committee, over 330 delegates being registered, that a new hall had to be booked a few days before the meeting to provide sufficient seating. The result of this was that tea and coffee could not be provided and the delegates were not as comfortable as one would have hoped, but despite these shortcomings the meeting was highly successful. The Gas Chromatography Symposium in Edinburgh was organised jointly with the Gas Chromatography Discussion Group, and a great deal of help was given by the Scottish Section of the Society. It was by far our most ambitious project and 560 delegates were attracted, 160 of them from overseas.Apart from the scientific programme an exhibition of commercial equipment was organised and receptions were hleld for delegates and their ladies on three evenings. Two of these functions were given by the Lord Provost of Edinburgh and the British Petroleum Company, respectively. A ladies’ programme of visits to local industries and beauty spots was arranged, and on the final d.ay the delegates had an opportunity to visit Scottish industries. The proceedings of all these three Symposia were published in book form. The Committee intends to continue a policy of close co-operation with other Groups and hopes that Society members will give full support to these activities. THE ANALYsT-The Council and the Publication Committee have continued to consider The Analyst and to seek ways in which its value to analysts can be enhanced. Innovations during the year include the publication of an irnportant general lecture on “The Changing Aspect of Chemical Analysis,” originally given by H.N. Wilson to the North of England Section in October, 1959, and it is hoped that other lectures of a similar calibre will follow. This is in addition to the biennial Bernard Dyer ldemorial Lecture, given in 1960 by Professor A. C. Frazer, which was published in May. The first of the monographs forecast in last year’s Report will appear shortly; it is on “Methods for the Analysis of Non-soapy Detergent Pro- ducts,” by G.F. Longman and J. Hilton. The Publication Committee has compared the numbers of papers in various fields of analysis published in The Analyst with the numbers of abstracts in the same fields appearing in Analytical Abstracts during the corresponding period. In this comparison with world analytical literature, it appears that The Analyst carries its fair share of papers on most topics. The Publication Committee is also discussing the sources from which papers come with a view to taking steps to increase the num’ber of papers from certain quarters. This is greater than any previous volume except that for 19514, which in addition to its normal contents contained the full proceedings of the International Congress on Analytical Chemistry held that year a t Oxford. More papers and notes were published in 1960 than ever before: 118 and 66, respectively, compared with 89 and 52 in 1959. As last year, six Review Papers are included in this total, and also two Reports to tlhe Analytical Methods Committee on Special Researches and one Lecture of general interest. The number of copies of each issue being printed is 6900. Summaries of 28 papers presented a t meetings but not being published in full anywhere were printed in the Proceedings of the Society. Fifty-six books were reviewed. Fifteen issues of the Bulletin were distributed with The Analyst during the year. Although it is published only when there are announceme:nts to be made, the Bulletin has appeared in all twelve months this year (two in each of the first three months); this has been brought about by the increasing activity throughout the year of the Society, its Sections and its Groups. The 1960 volume of The Analyst contained 928 pages, against 756 in 1959. ANALYTICAL ABSTRACTS-The steady growth of Analytical Abstracts has continued during the year in spite of difficulties of maintaining an adequate staff. The number of abstracts published in Volume 7 was 5522, contained in 732 pages, as compared with 5073May, 19611 ANNUAL REPORT OF COUNCIL: MARCH, 1961 297 abstracts in 692 pages in 1959. In spite of this the number of abstracts remaining unpublished, and consequently the interval between publication of the original paper and the abstract, has not been substantially reduced; this interval is now on the average about eight months. The Index for 1959 was published on April 27th, which was the scheduled date, a month earlier than in the previous year. Although the printing number for 1960 was fixed at 6800, stocks have been reduced almost to vanishing point owing to the fact that sales have increased to an unexpectedly high figure. The membership of the Abstracts Committee remains unchanged, R. C. CHIRNSIDE, President. R. E. STUCKEY, Honorary Secretary.

ISSN:0003-2654    

DOI:10.1039/AN9618600286

出版商:RSC    

年代:1961

数据来源: RSC

摘要:

May, 19611 ANNUAL REPORT OF COUNCIL: MARCH, 1961 297 Report of the Analytical Methods Committee 1960 THIS sixth Report of the Analytical Methods Committee of The Society for Analytical Chemistry reviews the progress of work during 1960; however, the period covered is from March 1st to December 31st, ie., ten months only. ANALYTICAL METHODS COMMITTEE Chairman: D. C. Garratt, Ph.D., D.Sc., F.R.I.C. Boots Pure Drug Co. Ltd. A. J . Amos, BSc., Ph.D., F.R.I.C. R. Belcher, Ph.D., DSc., F.Inst.F., F.R.I.C. E. Bishop, BSc., A.R.C.S.T., A.R.I.C. R. C. Chirnside, F.R.I.C. J. H. Hamence, M.Sc., Ph.D., F.R.I.C. W. C. Johnson, M.B.E., F.R.I.C. D. W. Kent-Jones, BSc., Ph.D., F.R.I.C. E. Q. Laws, BSc., F.R.I.C. R. F. Milton, B.Sc., Ph.D., M.I.Biol., F.R.I.C. W. H. Simmons, B.Sc., M.Inst.Pet., F.R.I.C.* A.A. Smales, B.Sc., F.R.I.C. R. E. Stuckey, Ph.D., DSc., F.P.S., F.R.I.C. C. Whalley, B.Sc., F.R.I.C. K. A. Williams, BSc., Ph.D., A.Inst.P., H. N. Wilson, F.R.I.C. Imperial Chemical Industries Ltd. (Billingham J. Haslam, DSc., F.R.I.C. Imperial Chemical Industries Ltd. (Plastics Analytical and Consulting Chemist (Honorary University of Birmingham (Professor of Analytical University of Exeter (Department of Chemistry) President of the Society Public Analyst, Oficial Agricultural Analyst and Consulting Chemist Hopkin & Williams Ltd. Analytical and Consulting Chemist D.S.I.R., Laboratory of the Government Chemist Analytical and Consulting Biochemist Analytical and Consulting Chemist Atomic Energy Research Establishment, Harwell Honorary Secretary of the Society Laporte Chemicals Ltd.Analytical and Consulting Chemist Treasurer of the Society) Chemistry) M.Inst.Pet., F.R.I.C. Division) Division) Secretary: Miss C. H. Tinker, B.Sc., Ph.D., A.R.I.C. Assistant Secretary: Miss A. M. Parry, B.Sc. * Deceased December, 1960. GENERAL REVIEW The Committee was sorry to learn of the death in December of Mr. W. H. Simmons. Mr. Simmons’s long association with the Committee goes right back to its formation in 1924, when he became its first Honorary Secretary, an office he held until 1946, and he was also Chairman of the Essential Oils Sub-Committee from 1933 to 1956. On his retirement from the active work of the Sub-Committee he was elected an honorary member in recognition of his long and devoted service and in gratitude for all the valuable help and guidance he so willingly gave over the years.During the year, the Committee was sorry to lose, through resignation, Mr. W. T. Elwell, and the opportunity is taken here to thank him for his help.298 REPORT OF THE ANALYTICAL METHODS COMMITTEE 1960 [Vol. 86 During the year, also, the Committee was glad to welcome two ex-members, namely, Dr. J. Haslam and Dr. R. F. Milton, and a new member, Mr. E. Bishop. PROGRESS OF WORK- The Committee is again able to report steady progress in its work, as evidenced by the continued output of published reports and by #an increase in the number of committees, which now total 22, two more than last year. The willingness with which all members of committees have undertaken the tasks before them cannot be too highly rated, and their constant enthusiasm in collaborative tests in their own laboratories has made possible the successful development of the Committee’s work during the past few years.This is illustrated by the progress of work in the five panels dealing with methods for Additives in Animal Feeding Stuffs. The Sub-Committee responsible for co-ordinating the work of these panels was appointed a t the end of 1958 in response to a request for help from the Standing Advisory Committee, Fertilisers and Feeding Stuffs Act, 1926, of the Ministry of Agriculture, Fisheries and Food. It immediately set to work to review any methods that might be available for determining in the supplemented or medicated feed any of the large number of additives that are, or are likely to be, used.The list of additives to be considered was a formidable one, and, after the preliminary review of methods for the additives per se had shown that few, if any, of them could be applied to the determination of those additives when contained in the feed, a somewhat gloomy picture was presented in an Interim Report to the Ministry’s Advisory Committee at the end of 1959. Much investigational work was envisaged and the prospects of an early success in finding suitable methods were not par- ticularly encouraging. However, after a further year in which intensive collaborative work has been carried out, the outlook as presented in a second Interim Report to the Advisory Committee is much brighter. A number of methods can now be recommended (some with certain limita- tions), and the panels are at present engaged in preparing reports on the work carried out in connection with them: it is hoped that these reports will be published during the coming year.Meanwhile, collaborative investigations into methods for the remaining additives are proceeding, but success in these projects may not be so rapid, since the problems to be solved are acknowledged to be more difficult than in the first group. The r81e of a sixth panel of this Sub-committee, dealing with the group of mineral additives, was undertaken by the existing Sub-Committee engaged in the preparation of methods for determining Trace Elements in Fertilisers and Feeding Stuffs. This Sub- committee had already been in existence for about a year and a half before the Additives Sub-committee was appointed and, like the latter, had been set up as a result of an approach by the same Advisory Committee to the Ministry.The lengthy programme of work that it undertook is now virtually complete, methods, for 15 elements having been agreed upon. In a few cases more than one method is to be recommended for the same element, according to the level to be determined (the content in a fertiliser may differ markedly from that in a feeding stuff) and also according to the nature of the sample, since the types of ingredients may demand a different technique. The results of this Sub-Committee’s work are now being prepared as an integrated report, and it is hoped that this will be ready for publication within the next few months.Another Sub-committee to complete part of its programme of work is that engaged on methods for determining Metallic Impurities in Organic Matter. The term “organic matter” here covers a wide variety of materials and can be said to include any organic substance whose use is affected by the presence of toxic or deleterious traces of metals, e.g., foodstuffs, drugs, plastics, lubricating oils. For this reason, the Sub-committee aims at recommending a method that is satisfactorily selective for a particular trace metal and can be used in any normal up-to-date laboratory. Further, because the organic materials to be examined are of such diverse types, the correct preparation of the sample is of the utmost importance. The Sub-committee therefore decided that it would be expedient to make a comprehensive collection of accepted and reliable procedures for the destruction of the organic matter, arranged on a systematic basis and depending on the ease with which this can be achieved without loss of the metal to be determined.This has been done and the collected methods were published in the September, 1960, issue of The Analyst. Also in the same issue was the Sub-committee’s report on The Deter- mination of Small Amounts of Arsenic in Organic Matter. This report recommends a methodMay, 19611 REPORT OF THE ANALYTICAL METHODS COMMITTEE 1960 299 in which molybdenum blue is used, and it also includes a revision of the standard Gutzeit procedure. Another committee report to be published during the year was that by a panel of the Joint Conmiittee with the Pharmaceutical Society, on The Assay of Rauwolfia.Mention was made a year ago of the imminent completion of this panel’s programme of work, and the report was subsequently published in the October, 1960, issue of The AnaZyst. Two other reports mentioned last year as being in the press were concerned with special investigational work commissioned by the Analytical Methods Committee : both were subse- quently published in The Analyst during the year. One, on The Determination of Trace Quantities of Silver in Trade Effluents, appeared in the March issue, and describes the investigations carried out by Mr. T. R. Pierce at Oxford in an attempt to evolve a sufficiently sensitive method for determining down to 0.01 p.p.m. of silver in the presence of organic matter.The Joint Committee of The Society for Analytical Chemistry and the Association of British Chemical Manufacturers, whose book of collected Recommended Methods for the Analysis of Trade Effluents was published in 1958, had suggested that a suitable method should be sought, since silver (although it is an unlikely contaminant of trade effluents because of its economic value) adversely affects the anaerobic bacterial processes in sewage treatment and is toxic to fish and other aquatic life. As a result a method is recommended that satisfactorily concentrates and separates the silver, which is then determined absorptio- metrically. The other report, on An Investigation into the Use of Bioassay for Pesticide Residues in Foodstuffs, was by Mr.P. H. Needham, who made an extensive survey of the extent to which bioassays are used in laboratories in the United Kingdom and in European countries as a rapid “screening” test for detecting or determining toxic residues. Mr. Needham’s report was published in the November issue of The AnaZyst, having previously formed the basis of an evening discussion meeting organised by the Biological Methods Group of the Society in October. The results of this survey were most illuminating, because they showed that bioassay techniques involving small arthropods are being used much more extensively than had been suspected from a scrutiny of the literature. This was due to the fact that most of the laboratories have developed internally their own techniques to suit individual requirements -usually to give a quick comparative assessment of the toxicity of samples in which the identity of the pesticide is known.Although some investigational work, principally in continental laboratories, is being done in an attempt to use bioassay as a qualitative “screen- ing” test for foodstuff samples in which the identity of the pesticide is unknown, most laboratories still rely on chemical and chromatographic methods for identification purposes : in only one laboratory that was visited was any attempt being made to develop a biological technique for classifying pesticides into groups. The need for a rapid sorting test has been evident for some time, since the usual chemical methods for identifying or assaying pesticide residues in foods are so lengthy as to be of little value for use on perishable foodstuffs.Mr. Needham’s survey showed the considerable potentialities of bioassay techniques, but it was clear that a considerable amount of stan- dardisation would be required before bioassay could be used on a more general basis. Further consultation with representatives of laboratories using bioassays indicated that research work would first be needed to establish the correct conditions of breeding and use of a selected number of organisms and to determine their comparative sensitivities towards certain pesticides. A second stage of investigational work would be to ascertain the best methods of preparing foodstuff samples for bioassay to avoid extraneous toxic effects. As a result, it was decided that the Society should appoint a research scholar to initiate this work of standardisation, and it was encouraging to learn that a number of laboratories in this country were willing to co-operate in any way possible.At the beginning of November, therefore, Dr. J. H. Stevenson, an entomologist, was appointed as the Society’s Scholar to undertake this work at Rothamsted Experimental Station under the general guidance of Mr. Needham, and the Society is most grateful to the Director of the Station for his generosity in providing the necessary facilities. Two other reports to be published during the year are those on Recommended Methods of Analysis of Pesticide Residues in Foodstuffs. Early in 1958, two Panels were set up jointly by the Society for Analytical Chemistry (represented by the Analytical Methods Committee), the Scientific Sub-committee of the Interdepartmental Advisory Committee on Poisonous Other possible techniques are also described.300 REPORT OF THE ANALYTICAL M:ETHODS COMMITTEE 1960 [Vol.86 Substances Used in Agriculture and Food Storage and the Association of British Insecticide Manufacturers (now the Association of British Manufacturers of Agricultural Chemicals). These two Panels undertook collaborative studie:; of analytical methods for DDT and BHC residues. Later, in 1959, two more Joint Panels were set up to study methods for deter- mining malathion and organo-mercury residues. Of these four Panels, those concerned with DDT and malathion have completed their programmes of work, and their reports were published, respectively, in the August and December issues of The AmaZyst.Recently it has been agreed to set up two more Joint Panels-on fluoracetamide and Phosdrin residues. Mention was made earlier in this Report of the appointment of new committees during the year. One of these is undertaking a critical examination of the various substances that have been proposed for use as primary standards in acidimetry and alkalimetry, and it has been set up as a result of a request from the Analytical Chemistry Section of the International Union of Pure and Applied Chemistry for recommendations of suitable substances-these recommendations to be made on behalf of the United Kingdom. Since a similar programme of work for primary standards as a whole had been proposed for consideration by the Micro- chemistry Group of the Society, it was agreed to amalgamate the work into a single Sub- committee under the aegis of the A.M.C., since the personnel of both committees would be virtually the same.The Sub-committee, with Mr. E. Bishop as Chairman, began its work in June; a classification of the various proposed standards has been made, and these are being examined critically with a view to evaluating them according to certain criteria. The second committee to be appointed is concerned with the assay of crude drugs being undertaken by the Joint Committee with the Pharmaceutical Society. This particular Panel is examining the various biological techniques used for the assay of anthraquinone drugs (senna, cascara, aloes, etc.), since it was found that the existing Panel Concerned with methods for the chemical assay of these substances could not usefully proceed until some measure of agreement of results obtained by different bioassay methods could be established.A third new Sub-committee of the A.M.C. is also to be appointed as soon as possible to make a comprehensive review of Methods for Particle Size Analysis, with a view to evaluating the various principles underlying the instrumental methods used for determinations of particle size in the sub-sieve range. This Sub-Committee will be under the chairmanship of Mr. E. Q. Laws. The other Sub-committees and Panels have continued to make progress during the year, and details of their personnel and reports of work will be found below. ANALYTICAL METHODS TRUST- The number of industrial organisations that gave donations to the Trust Fund during the year was 32 (the same as in 1959) and the tota.1 amount received was approximately l4500, This sum represents approximately E400 less in subscriptions than in 1959.INCOME AND EXPENDITURE- The statement of accounts (see Appendix 1:) for the financial year ending October 31st, 1960, shows an expenditure of E4577 (including Scholarship Grants and Awards for Research). The gross income of k6283 includes k955 income tax recovered on Covenanted Subscriptions over a period of five years. REPORTS OF SUB-COAIMITTEES OF THE ANALYTICAL METHlODS COMMITTEE PUBLICATIONS SCB-COMMITTEE CONSTITUTION- D. C . Garratt, Ph.D., D.Sc., F.R.I.C. J. B. Attrill, M.A., F.R.I.C. J. H. Hamence, M.Sc., Ph.D., F.R.I.C.D. W. Kent-Jones, B.Sc., Ph.D., F.R.I.C. H. N. Wilson, F.R.I.C. S. C. Jolly, BSc., B.Pharm., M.P.S., A.R.I.C. Chairman, Analytical Methods Committee Editor, The Analyst Member, Analytical Methods Committee Member, Analytical Methods Committee Member, Analytical Methods Committee Editov, Scientijk Publications, The Phnrmaceuti- (Chairman) (Secretary) cal Society of Great Britain PROGRESS OF WORK- Progress has been made on the preparatory editorial work necessary for the publication in 1961 of the proposed book of Standard Methods of Analysis, which is to consist of aMay, 19611 REPORT OF THE ANALYTICAL METHODS COMMITTEE 1960 301 collection of the recommended methods of analysis included in the published Reports of the various Sub-committees and Joint Committees, together with a bibliography based on that published by the Analytical Methods Committee in 1951.The revision and expansion of this bibliography has been started and should be completed early in 1961. CONSTITUTION- ADDITIVES IN ANIMAL FEEDING STUFFS SUB-COMMITTEE D. C. Garratt, Ph.D., D.Sc., F.R.I.C. A. J. Amos, B.Sc., Ph.D., F.R.I.C. J. H. Hamence, MSc., Ph.D., F.R.I.C. R. F. Phipers, B.Sc., Ph.D. S. A. Price, B.Sc., F.R.I.C. C. J. Regan, B.Sc., F.R.I.C. Formerly Chemist-in-Chief, London County W. L. Sheppard, F.R.I.C. R. E. Stuckey, Ph.D., D.Sc., F.P.S., F.R.I.C. F. R. Williams Miss C. H. Tinker (Secretary) Boots Pure Drug Co. Ltd. Analytical and Consulting Chemist Public Analyst, Oficial Agricultural Analyst and Cooper Technical Bureau Vitamins Ltd.(Chairman) Consulting Chemist Council Unilever Ltd. British Drug Houses Ltd. Ministry of Agriculture, Fisheries and Food TERMS OF REFERENCE-“TO investigate and prepare methods for determining the amounts of additives (nutrients, stimulants and prophylactics) in animal and poultry feeding stuffs.” PROGRESS OF WORK- The general progress of work in the Sub-committee and in its six Panels has been reviewed earlier in this Report (see p. 298), and the detailed reports of the Panels are given below. The question of animal dietetics is receiving a considerable amount of attention these days, and there is an increasing demand for adequate methods of analysis for the control of feeding stuffs; at a Symposium on “Analytical Chemistry in the Service of Agriculture” organised by the Society at Nottingham in July, 1960, the Sub-committee’s work in this connection was presented in a paper by Dr.R. F. Phipers, Chairman of the Prophylactics Panel. ANTIBIOTICS PANEL CONSTITUTION- S. A. Price, B.Sc., F.R.I.C. A. J. Cavell, M.Sc., A.R.C.S., D.I.C., F.R.I.C. Ministry of Agriculture, Fisheries and Food, National Agricultural Advisory Service Mrs. J. Gammon, BSc. (ne’e Stephens) Cyanamid of Great Britain Ltd., Lederle Labora- tories 0. Hughes Pfzer Ltd. W. P. Jones, F.P.S., F.R.I.C. Cyanamid of Great Britain Ltd., Lederle Labora- tories G. Sykes, M.Sc., F.R.I.C. Boots Pure Drug Co. Ltd. J. H. Taylor, Ph.D., M.R.C.V.S. Cyanamid of Great Britain Ltd. , Agricultural S. Varsanyi, A.I.S.T. Glaxo Laboratories Ltd. Miss A. M.Parry (Secretary) Vitamins Ltd. (Chairman) Division PROGRESS OF WORK- Early in its work the Panel confirmed that each of the three antibiotics, penicillin, aureomycin and oxytetracycline, could be assayed by chemical or microbiological methods in their respective pre-mixes (it?., at the level of a few grams per pound). Chemical methods are not applicable at the levels at which antibiotics are added to feeding stuffs (a few grams per ton), and the Panel has therefore examined microbiological methods with a view to recommending procedures that would be similar for all three anti- biotics. Methods have now been agreed upon by which reproducible results can be obtained on feeding stuffs containing any one of the three antibiotics. However, these methods require a sample of the unfortified feed for use as a blank; since in normal practice this is unlikely to be available, investigations are now in progress on procedures for producing a “blank” by destruction of the antibiotic in the fortified sample.The development of methods for the assay of samples containing more than one antibiotic and those containing additives, such as prophylactics or other drugs, in addition to the antibiotic will require more extensive investigations and probably original research.302 CONSTITUTION- REPORT OF THE ANALYTICAL METHODS COMMITTEE 1960 HORMONES PANEL R. E. Stuckey, Ph.D., D.Sc., F.P.S., F.R.I.C. J. Allen, A.R.I.C. L. Brealey, B.Sc. J. A. Potter, A.R.I.C. W. L. Sheppard, F.R.I.C. Miss A. M. Parry (Secretary) British Drug Houses Ltd. British Drug Houses Ltd. Boots Pure Drug Co.Ltd. Analytical and Consulting Chemist Unilever Ltd. (Chairman) [Vol. 86 PROGRESS OF WORK- Chemical methods for the assay of stilboestrol and hexoestrol in feeding stuffs have been examined and tested collaboratively. The methods are now considered to be satisfactory and reports are being prepared. PROPHYLACTICS PANEL CONSTITUTION- R. F. Phipers, B.Sc., Ph.D. C. W. Ballard, B.Sc., F.P.S., F.R.I.C. N. C. Brown, M.A., B.Sc., A.R.I.C. H. G. Dickenson, B.Sc., Ph.D. A. W. Hartley, F.R.I.C. A. Holbrook, F.R.I.C. . (Chairman) S. G. E. Stevens, B.Sc., F.R.I.C. J. A. Stubbles, B.Sc. Miss A. M. Parry (Secretary) Cooper Technical Bureau M a y & Baker Ltd. Cooper Technical Bureau Ward, Blenkinsop & Co. Ltd. Spillers Ltd. Imperial Chemical Industries Ltd. (Pharma- Smith Kline 6 French Laboratories Ltd.M a y & Baker Ltd. ceuticals Division) PROGRESS OF WORK- The use of complex feeding stuffs in collaborative assays revealed the need for further modification of the method for nitrofurazone, but the Panel now considers the method to be satisfactory, and a report is being prepared. Sirriilarly, the colorimetric method for the assay of sulphaquinoxaline was found to be inapplicable to certain feeding stuffs, and collaborative work on the sulpha drugs has therefore been deferred pending the outcome of investigations by one member of the Panel into a paper-chromatographic method of separation. After preliminary trials by individual members of the Panel, methods are now being considered for the assay of nicarbazin and of acinitrazole, and collaborative tests on the latter are in progress.The Panel is keeping under review the introduction and use of new coccidiostats and anti-blackhead drugs and will, as necessary, revise the list of prophylactics to be investigated. VITAMINS (FAT-SOLUBLE) PANEL CONSTITUTION- W. L. Sheppard, F.R.I.C. L. Brealey, B.Sc. C. R. Louden, B.Sc., F.R.I.C. H. Pritchard, M.Sc., F.R.I.C. S. A. Reed, B.Sc., A.R.I.C. G. Walley, B.Sc., F.R.I.C. J..Williams, BSc., Ph.D., F.R.I.C. Miss C. H. Tinker (Secretary) (Chairman) Unilever Ltd. Boots Pure Drug Co. Ltd. R. Silcock G. Sons Ltd. Analytical and Consulting Chemist British Cod Liver Oils (Hull and Grimsby) Ltd. Unilever Ltd. Spillers Ltd. PROGRESS OF WORK- No meetings of this Panel were held during the year, but collaborative tests have nevertheless continued, and the Panel is now satisfied that the spectrophotometric method is suitable, provided that strict attention is given to procedural detail, for the determination of vitamin A and of /3-carotene in most types of feeding stuffs.The Panel’s report is now being prepared, and it is hoped to publish it shortly. Meanwhile, further collaborative work has been proceeding in the hope that an alternative quick method can be included in the report ; this method depends on the formation of anhydro-vitamin A, which is determined colorimetrically .May, 19611 REPORT OF THE ANALYTICAL METHODS COMMITTEE 1960 VITAMINS (WATER-SOLUBLE) PANEL CONSTITUTION- 303 A. J. Amos, BSc., Ph.D., F.R.I.C.J. E. Ford, BSc., Ph.D. B. M. Gibbs, B.Sc., A.R.I.C. S. A. Price, BSc., F.R.I.C. H. Pritchard, MSc., F.R.I.C. F. Clermont Scott, BSc., F.R.I.C. G. Sykes, M.Sc., F.R.I.C. S. Varsanyi, A.I.S.T. J. Williams, BSc., Ph.D., F.R.I.C. Miss C. H. Tinker (Secretary) (Chairman) Analytical and Consulting Chemist National Institute f o r Research in Dairying Unilever Ltd. Vitamins Ltd. Analytical and Consulting Chemist Vitamins Ltd. Boots Pure Drug Co. Ltd. Glaxo Laboratories Ltd. Spillers Ltd. PROGRESS OF WORK- Accepted methods for the following B-group vitamins have been investigated to ascertain whether or not they can be made applicable to the determination of those vitamins when present at low concentration in feeding stuffs: nicotinic acid; vitamin BIZ; pantothenic acid ; riboflavin; pyridoxin (vitamin B6) ; and choline. For all these vitamins microbiological methods have been investigated, but chemical methods for pyridoxin and choline are also under consideration.For the first three vitamins in the above list-nicotinic acid, vitamin BI2 and pantothenic acid-methods can now be recommended for use in feeding-stuff assays, the order of accuracy of the determinations being about 30 per cent. in the hands of experienced microbiologists. It is hoped that these reports will be published shortly. In all tests the total vitamin is determined, i.e., naturally occurring plus added vitamin. However, the total reported may not necessarily be a measure of the biological value of the feeding stuff as a source of the vitamin in question, since it is known that in some instances the naturally occurring vitamin may be present in a “bound” form.For instance, nicotinic acid can occur as a bound form in cereal products, and this, though unavailable to the domestic animal, is extracted completely during the normal assay procedure; on the other hand, some bound forms of naturally occurring pantothenic acid may not be wholly available to the test organism unless a special dual-enzyme system is employed for extraction. Methods for the remaining three vitamins-riboflavin, pyridoxin and choline-are still under investigation. For riboflavin, although reproducible results were obtained by all the Panel members when assaying the same extract, the extraction procedure itself requires more investigation than the Panel members can carry out on a collaborative basis, and this is being looked into privately by one of the laboratories concerned.ANALYTICAL STANDARDS SUB-COMMITTEE CONSTITUTION- E. Bishop, B.Sc., A.R.C.S.T., A.R.I.C. (Chairman) P. R. W. Baker, M.Sc., A.R.I.C. A. G. Hill, F.R.I.C. R. M. Pearson, A.R.I.C. Imperial Chemical Industries Ltd. (Billingham W. I. Stephen, BSc., Ph.D., A.R.I.C. University of Birmingham (Department of C. Whalley, BSc., F.R.I.C. J. T. Yardley, BSc., F.R.I.C. Miss A. M. Parry (Secretary) University of Exeter (Department of Chemistry) Wellcome Research Laboratories British Drug Houses Ltd. Division) Chemistry) Lnporte Chemicals Ltd. Hopkin G. Williams Ltd. (de9uty S . Andrus, A.R.I.C.) TERMS OF REFERENCE-“TO examine existing analytical standards and to select suitable substances.” PROGRAMME OF WORK- As mentioned earlier in this Report (see p. 300), this Sub-committee was set up in response to a request from the Analytical Chemistry Section of the International Union of Pure and Applied Chemistry that a critical examination be made of the various substances that have been proposed for use as primary standards in acidimetry and alkalimetry, with304 REPORT OF THE ANALYTICAL METHODS COMMITTEE 1960 [Vol. 86 a view to making recommendations on behalf of the United Kingdom. Work on titrimetric standards in general, which was being considered by the Microanalytical Reagents and Stan- dards Sub-committee of the Microchemistry Group of the Society, will also be undertaken by the present Sub-committee.The substances submitted to the Sub-committee for consideration in the first place were listed in two groups, (a) established standards and (b) newer proposed standards, as follows- (a) Established standards (b) New standards Sodium carbonate Constant-boiling hydrochloric acid Borax Potassium hydrogen phthalate Sulphamic acid Potassium bi-iodate Benzoic acid Sodium hydrogen diglycollate 2,4,6-Trinitrobenzoic acid Sulphuric acid 3,3’-Dinitrosulphimide Calcium hydrogen malate hexahydrate 4-Aminop yridine Tris (hydroxymethyl) aminomethane Potassium hydrogen 3,5-dinitrobenzoate Hydrazine sulphate was added to list (a) at the Sub-committee’s first meeting in June, 1960. PROGRESS OF WORK- Since its first meeting in June, 1960, the Sub-committee has defined its objectives as (a) To survey existing standard substances suitable for acid - base titrimetry. follows- (b) To classify these according to (i) their purity, (ii) their facility of preparation and handling and (iii) their titrimetric application.(c) To select one or more substances for recommendation as reference standards in compliance with the I.U.P.A.C. referendum. (a) To draw up specifications for the pre:paration, handling, purity and use of the standards chosen. (e) To draw up specifications within their own categories for other substances found suitable for general application. Reports prepared by members on each of the established standards, and on some of the newer ones, have enabled the Sub-committee to evaluate the suitability of these substances as primary standards and to select the most promising for immediate examination.Collabora- tive tests on the first phase of the experimental. work are being designed. CHLORINE IN ORGANIC COM:POUNDS SUB-COMMITTEE CONSTITUTION- R. Belcher, Ph.D., D.Sc., F.Inst.F., F.R.I.C. (Chairman) J. H. Dunn, B.Sc., A.R.I.C. K. Gardner, BSc., F.R.I.C. R. Goulden, F.R.I.C. C. A. Johnson, BSc., B.Pharm., F.P.S., F.R.I.C. Miss A. M. G. Macdonald, M.Sc., Ph.D., A.R.I.C. Miss C. H. Tinker (Secretary) University of Birmingham (Professor of Analytical Chemistry) Plant Protection Ltd. Fisons Pest Control Ltd. “Shell” Research Ltd. Boots Pure Drug Co. Ltd. University of Birmingham (Department of Chemistry) TERMS OF REFERENCE-“TO prepare methods for the determination of organically-bound chlorine, having special reference to commercial preparations such as pesticides.” PROGRESS OF WORK- The Sub-committee met only once during the year.The application of the oxygen flask combustion method to the semi-micro determination of organically bound chlorine in technical grades of pesticides and in solid and liquid formulations is considered satisfactory for products containing not less than 10 per cent. of chlorine, but not for low-concentrate dusts, since the high proportion of inorganic filler prevents complete combustion. The Sub-committee’s report on its investigations, together with details of the recommended analytical procedure, is to be prepared for publication.May, 19611 REPORT OF THE ANALYTICAL METHODS COMMITTEE 1960 306 ESSENTIAL OILS SUB-COMMITTEE CONSTITUTION- G.W. Ferguson, B.Sc., Ph.D., F.R.I.C. A. J. M. Bailey, B.Sc., F.P.S., F.R.I.C. D. Holness, B.A. H. T. Islip, B.Sc., F.R.I.C. P. McGregor, B.Sc., A.H.-W.C., F.R.I.C. T. L. Parkinson, B.Sc., Ph.D., F.R.I.C. Miss H. M. Perry, M.Sc., F.R.I.C. G. B. Pickering, B.Sc., Ph.D. J. H. Seager, M.Sc., F.R.I.C. S. G. E. Stevens, B.Sc., F.R.I.C. B. D. Sully, B.Sc., Ph.D., A.R.C.S., F.R.I.C. Miss C. H. Tinker (Secretary) Analytical and Consulting Chemist W. J . Bush 6 Co. Ltd. Proprietary Perfumes Ltd. Formerly D.S. I.R., Tropical Products Institute D.S.I.R., Laboratory of the Government Chemist Beecham Foods Ltd. Stafford Allen & Sons Ltd. D.S.I.R., Tropical Products Institute Yardley & Co. Ltd. Smith Kline 6 French Laboratories Ltd. A . Boake, Roberts & Co.Ltd. (Chairman) PROGRESS OF WORK- In the Sub-committee’s Report on the Determination of Linalol, published in 1957, the Glichitch method was recommended as being preferable to the Fiore method. Subse- quently, however, one of the Sub-committee members has conclusively demonstrated by the use of gas - liquid chromatography that the mechanism of the Fiore method is the sounder (Holness, D., Analyst, 1959, 84, 3). The Sub-committee therefore decided to reverse its original recommendation, and an Amendment to the 1957 Report has been published accord- ingly (AnaZyst, 1960, 85, 165). This use of gas-liquid chromatography for tracing the course of certain chemical reactions has already been applied by the Sub-committee to demonstrate the inaccuracies of hot-formylation methods for determining citronellol (Analyst, 1959, 84, 690).The Sub-committee is continuing its collaborative investigations of various methods for the determination of citral and of carbonyl compounds. MEAT PRODUCTS SUB-COMMITTEE CONSTITUTION- S. M. Herschdoerfer, Ph.D., F.R.I.C. S. Back, B.Sc., F.R.I.C. Miss E. M. Chatt, B.Sc., F.R.I.C.* P. 0. Dennis, B.Sc., F.R.I.C. J. R. Fraser, B.Sc., A.C.G.F.C., F.R.I.C. R. A. Lawrie, B.Sc., Ph.D., F.R.I.C. A. McM. Taylor, BSc., Ph.D., F.R.I.C. E. F. Williams, M.A., F.R.I.C. H. Amphlett Williams, Ph.D., A.C.G.F.C., F.R.I.C. Miss C. H. Tinker (Secretary) T. Wall.& Sons Ltd. Crosse & Blackwell Ltd. British Food Manufacturing Industries Research 0 x 0 Ltd. D.S.I.R., Laboratory of the Government Chemist A .R.C..Low Temperature Research Station British Food Manufacturing Industries Research J . Sainsbury Ltd. Public Analyst (Chairman) Association Association (deputy H. C. Hornsey, F.R.I.C.) * Resigned July, 1960. TERMS OF REFERENCE-“(LZ) The determination of the meat content of products containing meat; (b) the determination of the constituents of meat and meat products. NOTE-The term ‘meat products’ to include hydrolysed protein and, if found necessary, fish pastes.” PROGRESS OF WORK- A year ago it was announced that the Sub-committee had prepared an interim report on nitrogen factors for pork. However, in view of the receipt of additional data from various meat research organisations in this country and in Europe, together with some data for the nitrogen content of rusk filler made from present-day flour, the Sub-committee decided to expand the report considerably and to add a short report on rusk filler. This has now been completed, and it is hoped to publish the full report shortly.Meanwhile, similar data on the nitrogen contents of beef, veal and chicken meat are being collected.306 REPORT OF THE ANALYTICAL METHODS COMMITTEE 1960 [Vol. 86 METALLIC IMPURITIES IN ORGANIC MATTER SUB-COMMITTEE CONSTITUTION- W. C. Johnson, M.B.E., F.R.I.C. Hopkin 6 Williams Ltd. L. Brealey, B.Sc. Boots Pure Drug Co. Ltd. Miss E. M. Chatt, B.Sc., F.R.1.C.. British Food Manufacturing Industries Reseavch J. C. Gage, B.Sc., Ph.D., F.R.I.C. Imperial Chemical Industries Ltd. (Industrial T. T. Gorsuch, BSc., Ph.D., A.R.I.C. U. K. Atomic Energy Authority, The Radiochemi- E.I. Johnson, M.Sc., F.R.I.C. D.S. I.R., Laboratory of the Government Chemist Miss E. M. Johnson, MSc. British Food Manufacturing Industvtes Research T. McLachlan, D.C.M., A.C.G.F.C., M.I.Biol., Public Analyst R. F. Milton, B.Sc., Ph.D., M.I.Biol., F.R.I.C. Analytical and Consulting Biochemist E. J. Newman, BSc., A.R.I.C. Hopkin & Williams Ltd. W. G. Sharples, A.R.I.C. Imperial Chemical Industries Ltd. (Dyestufls Miss A. M. Parry (Secretary) (Chairman) Association Hygiene Laboratories) cal Centre Association F.R. I.C. t Division) * Resigned July, 1960. t Resigned October, 1960. TERMS OF REFERENCE-"TO investigate the determination of small quantities of metals in organic matter." PROGRESS OF WORK- As mentioned earlier in this Report (see p.298), two reports from the Sub-committee were published in the September issue of The Analyst, namely, The Determination of Arsenic in Small Amounts of Organic Matter, containing details of a method in which molybdenum bIue is used and of the Gutzeit procedure, and Methods for the Destruction of Organic Matter, in which are assembled methods for both wet and dry decomposition, which are in general use and are of fairly wide applicability. The Sub-committee has considered the relative merits of a number of reagents and methods recognised for the determination of copper ; because a recommended method should be as widely applicable as possible both in selectivity and sensitivity, comparative tests are being carried out before a decision is made as to the most suitable method.Several methods are under review for the determination of mercury, since it is unlikely that a single method will be applicable to all types of sample. The Sub-committee is being kept informed of the work of the following bodies- Trace Elements in Fertilisers and Feeding Stiiff s Sub-committee. Mercury Residues Panel set up jointly by the Scientific Sub-committee on Poisonous Substance used in Agriculture and Food Storage, the Analytical Methods Committee and the Association of British Manufacturers of Agricultural Chemicals. DIRECT MICRO-DETERMINATION OF OXYGEN CONSTITUTION- D. W. Wilson, M.Sc., F.R.I.C. P. R. W. Baker, M.Sc., A.R.I.C. Miss B. B. Bauminger, Ph.D., A.I.R.I., F.R.I.C. W. T. Chambers, B.Sc., Ph.D., A.R.I.C. A. F. Colson, B.Sc., Ph.D., F.R.I.C.Miss M. Corner, B.Sc., F.R.I.C. Miss J. Cuckney F. Ellington, B.Sc., A.R.C.S., F.R.I.C. F. J. McMurray M. P. Mendoza, B.Sc., A.R.C.S. F. H. Oliver H. J . Warlow C. Whalley, BSc., F.R.I.C. Miss C. H. Tinker (Secretary) (Chairman) I N ORGANIC MATTER SUB-COMMITTEE Sir John Cuss College (Department of Chmistry) Wellcome Research Laboratories Dunlop Research Centre British Rubber Producers' Research Association Imperial Chemical Industries Ltd. (Alkali D.S. I.R., National Chemical Laboratory Imperial College of Science and Technology National Coal Board, Coal Research Establish- Wellcome Chemical Works British Coal Utilisation Research A ssociation Parke, Davis 6 Co. D.S.I.R., Tropical Products Institute Laporte Chemicals Ltd. Division) (Department of Chemistry) mentMay, 19611 REPORT OF THE ANALYTICAL METHODS COMMITTEE 1960 307 TERMS OF REFERENCE-“TO investigate the Unterzaucher method, and its modifications, for the micro-determination of oxygen.” PROGRESS OF WORK- The Sub-committee has carried out preliminary collaborative tests on the final stage of the method-Le., the reaction between pure carbon monoxide and iodine pentoxide-and, as a result of these tests, a statistically planned experiment is being devised.PESTICIDES RESIDUES IN FOODSTUFFS SUB-COMMITTEE CONSTITUTION- R. A. E. Galley, B.Sc., Ph.D., A.R.C.S., D.I.C., J. C. Gage, B.Sc., Ph.D., F.R.I.C. Imperial Chemical Industries Ltd. (Industrial D. C . Garratt, Ph.D., D.Sc., F.R.I.C. G. S. Hartley, DSc. C. 0. Harvey, BSc., A.R.C.S., F.R.I.C. J.G. Reynolds, F.Inst.Pet., F.R.I.C. Miss C . H. Tinker (Secretary) “Shell” Research Ltd. F.R.I.C. (Chairman) Hygiene Laboratories) Boots Pure Drug Co. Ltd. Research Centre of Fisons Pest Control Ltd, D.S.I.R., Laboratory of the Government Chemist “Shell” Research Ltd. TERMS OF REFERENCE-“TO consider the analytical problems that arise, or may arise, in connection with the presence of pesticide residues in foodstuffs; and to advise as to analytical procedures for the detection and determination of any such residues or their breakdown products.” PROGRESS OF WORK- This Sub-committee acts in an advisory capacity only and is not called upon to meet frequently. The progress of work on methods for pesticides residues has been covered in some detail earlier in this Report (see p.299)-research on bioassay methods being undertaken at Rothamsted Experimental Station by Dr. J. H. Stevenson under the direction of Mr. P. H. Needham, and collaborative testing of chemical methods being undertaken in collaboration with the Association of British Manufacturers of Agricultural Chemicals and the Scientific Sub-committee of the Interdepartmental Advisory Committee on Poisonous Substances used in Agriculture and Food Storage. TRACE ELEMENTS IN FERTILISERS AND FEEDING-STUFFS SUB-COMMITTEE CONSTITUTION- C. J. Regan, B.Sc., F.R.I.C. S. M. Boden, B.Sc., A.R.I.C. L. Brealey, B.Sc. S. G. Burgess, B.Sc., Ph.D., F.Inst.Pet., M.Inst.S.P., F.R.I.C. J. H. Hamence, M.Sc., Ph.D., F.R.I.C. E. I. Johnson, M.Sc., F.R.I.C. R. F. Milton, B.Sc., Ph.D., M.I.Biol., F.R.I.C.R. L. Mitchell, B.Sc., Ph.D., F.R.I.C., F.R.S.E. J. B. E. Patterson, M.Sc., F.R.I.C. W. L. Sheppard, F.R.I.C. J. Williams, B.Sc., Ph.D., F.R.I.C. Miss C. H. Tinker (Secretary) (Chairman) Formerly Chemist-in-Chief, London County Council Ministry of Agriculture, Fisheries and Food, National Agricultural A dvismy Servics Boots Pure Drug Co. Ltd. London County Council Public Analyst, Oficial Agricultural Analyst and Consulting Chemist D.S.I.R., Laboratory of the Government Chemist Analytical and Consulting Biochemist Macaulay Institute for Soil Research Ministry of Agriculture, Fisheries and Food, National Agricultural Advisory Service Unilever Ltd. Spillers Ltd. TERMS OF REFERENCE-“TO devise appropriate methods of analysis (to be recommended for inclusion in the Regulations under the Fertilisers and Feeding Stuffs Act, 1926) for the determination of boron, cobalt, copper, fluorine, iodine, iron, magnesium, manganese, molybdenum, selenium and zinc, which can be expected to be present in fertilisers and feeding stuffs.”308 REPORT OF THE ANALYTICAL METHODS COMMITTEE 1960 [Vol.86 A method for small amounts of selenium, which was causing some difficulty a year ago, is now con- sidered suitable for contents down to 2 pg when a colorimetric finish is used or down to 0-5 pg when a fluorimetric finish is used. In addition to its programme of work, as defined by the Terms of Reference, this Sub- committee also acts as the Minerals Panel of the Additives in Animal Feeding Stuffs Sub- committee (q.v.) and to this end has now agreed on methods for calcium and salt (as chloride).Methods for the determination of chromium and nickel in fertilisers are also to be recommended, since these elements may be present if sewage sludges are used. In all, some 18 methods have been completed, and a comprehensive report is being prepared for publication. PROGRESS OF WORK- Methods for all the 11 elements mentioned above have now been agreed upon. REPORT OF THE P.S. - S.A.C. JOINT COMMITTEE ON METHODS OF ASSAY OF CRUDE DRUGS MAIN COMMITTEE CONSTITUTION- Representing the Pharmaceutical Society of Great Brijain- K. R. Capper, Ph.D., B.Pharm., F.P.S., D.I.C. J. W. Fairbairn, BSc., Ph.D., F.P.S., F.L.S., R. Higson, F.P.S. W. Mitchell, B.Sc., Ph.D., F.R.I.C. Pharmaceutical Society of Great Britain University of London (Professor of Pharmacog- Ministry of Health, Supplies Division Stafford Allen & Sons Ltd.(Chairman) F.R.I.C. nosy) Representing the Society for Analytical Chemistry- C. A. Johnson, B.Sc., B.Pharm., F.P.S., F.R.I.C. H. C. Macfariane, A.R.T.C.S., F.R.I.C. D. Watt, F.P.S. D. C. Garratt, Ph.D., DSc., F.R.I.C. Boots Pure Drug Co. Ltd. Analytical and Consulting Chemist T. & H . Smith Ltd. Chairman of the Analytical Methods Committee (ex-oficio) Representing the Tropical Products Institute, D.S. I.12.- A. J. Feuell, B.Sc., Ph.D., A.R.I.C. Miss C. H. Tinker, BSc., Ph.D., A.R.I.C. Miss A. M. Parry, B.Sc. Secretary to the Analytical Methods Committee Assistant Secretary to the Analytical Methods (Secretary) (Assistant Secretary) Committee TERMS OF REFERENCE-"TO prepare standard methods of assay of crude drugs and kindred materials." PROGRESS OF WORK- The Main Committee, which acts in a steering capacity, is able to report steady progress in most of its working Panels.In two Panels, however, work has been suspended for the time being to enable some investigations outside their scope to be carried out elsewhere. The suspension of work by Panel 1, pending the outcome of research at Manchester Uni- versity on chemical and biological methods for diigitalis, was announced in last year's Report : the work of Panel 3, on chemical methods for anthraquinone drugs, has been suspended until a reliable biological assessment can be made; until this is achieved, it will not be possible to correlate the chemical methods under investigation.A new Panel, 3A, is undertaking the work on bioassay methods. The publication in October of the report on the Assay of Rauwolfia brought to an end the programme of work of Panel 4, and this has now been disbanded. Panels 2 and 5, on methods for capsicum and lonchocarpus, respectively, are continuing their investigations after the publication of their reports last year. The work of Panel 6,May, 19611 REPORT OF THE ANALYTICAL METHODS COMMITTEE 1960 309 on methods for pyrethrum, has progressed satisfactorily during the twelve months since the Panel’s appointment. Details of the progress by each Panel are given below. PANEL 1: Digitalis CONSTITUTION- H. Brindle, M.Sc., F.P.S., F.R.I.C. G. E. Foster, B.Sc., Ph.D., F.R.I.C. G. J. Rigby, M.Sc., Ph.D., Dip.Bact.K. L. Smith, M.P.S. J. P. Todd, Ph.D., F.P.S., F.R.I.C. W. D. Williams, B.Pharm., Ph.D., F.P.S. Miss A. M. Parry (Secretary) (Chairman) A.R.I.C. pU~$UY&Z-CHEMICAL METHOD Emeritus Professor of Pharmacy, University of Wellcome Chemical Works University of Manchester (Department of Phar- Boots Pure Drug Co. Ltd. Royal College of Science and Technology, Glasgow Royal College of Science and Technology, Glasgow Manchester macy 1 (Professor of Pharmacy) (School of Pharmacy) TERMS OF REFERENCE-“TO investigate chemical methods for the assay of digitalis and its preparations and to attempt to correlate them with the biological method of assay.” PROGRESS OF WORK- Research on the separation and assessment of the relative biological activities of the main constituents of digitalis leaf is being carried out by individual workers; meanwhile the work of the Panel has been suspended.PANEL 2 : CAPSICUM-CAPSAICIN CONTENT CONSTITUTION- H. B. Heath, M.B.E., B.Pharm., F.P.S. (Chairman) E. A. Elsbury, F.R.I.C. C. F. G. Fost, M.P.S. C. A. MacDonald, B.Sc., F.R.I.C. G. R. A. Short, F.P.S., F.L.S. G. I. Smales, B.Sc., A.R.I.C. Miss G. M. Wells, B.Sc., A.P.I. A. J. Woodgate, B.Sc. Miss A. M. Parry (Secretary) Stafford Allen & Sons Ltd. Parke, Davis G. Co. W. J . Bush G. Co. Ltd. Evans Medical Research Laboratories W. J . Bush & Co. Ltd. Parke, Davis G. Co. Beecham Research Laboratories Ltd. StaJfooYd Allen G. Sons Ltd. TERMS OF REFERENCE-I‘TO investigate methods of assay of capsicum and capsicum products with particular reference to the determination of the capsaicin content.” PROGRESS OF WORK- The Panel is now satisfied that its published methods for the determination of capsaicin (Analyst, 1959, 84, 603) can, with suitable modifications, be applied to capsicum wool and to highly coloured chillies: these modifications will be included in the Panel’s next report.Since paprika is used mainly as a colouring agent and not for its capsaicin content, there appears to be no need for a method of assaying it. The Panel is re-considering the colorimetric method for the assay of capsaicin. The published procedure, involving the preparation of the dry diazo compound, is known to be hazardous, and a variation of the method in which the salt is formed in solution is being investigated.A simplified spectrophotometric procedure, suitable for routine control tests, is also being examined. The methods already published do not distinguish between pure capsaicin and a synthetic eapsaicin-like derivative that is used in certain preparations. Investigations are proceeding into two possible methods, one by selective oxidation and the other by infra-red spectro- photometry, for differentiating between the vanillylamides of isodecanoic acid (capsaicin) and of nonylic acid (synthetic capsaicin). The Panel is grateful to Messrs. Pfizer Ltd. for gifts of samples of the pure vanillylamide of nonylic acid.310 REPORT OF THE ANALYTICAL METHODS COMMITTEE 1960 PANEL 3 : ANTHRAQUINONE DRUGS CONSTITUTION- W. Mitchell, BSc., Ph.D., F.R.I.C. Stafford Allen & Sons Ltd.IChairman) [Vol. 86 J. W: Fairbairn, BSc., Ph.D., F.P.S., F.L.S., C. A. Johnson, B.Sc., B.Pharm., F.P.S., F.R.I.C. S. C. Jolly, BSc., B.Pharm., M.P.S., A.R.I.C. Miss H. M. Perry, MSc., F.R.I.C. H. A. Ryan, BSc., F.R.I.C. W. Smith, BSc., F.R.I.C. R. V. Swann, B.Sc., F.R.I.C. Miss A. M. Parry (Secretary) University of London (Professor of Phavmacog- Boots Pure Drug Co. Ltd. Pharmaceutical Society of Great Britain Staflord Allen E Sons Ltd. Westminster Laboratories Ltd. Allen G. Hanburys Ltd. Allen G. Hanburys Ltd. F.R.I.C. nosy) TERMS OF REFERENCE-~~TO investigate methods for estimating the purgative activity of drugs and preparations of drugs containing aathraquinone derivatives with a view to recommending standard methods of assay.” PROGRESS OF WORK- After examination arid modification of a co:lorimetric chemical method for determining the sennoside content of samples of powdered senna pod, the Panel succeeded in obtaining reasonably good inter-laboratory agreement on samples of Alexandrian senna pods, but rather less satisfactory inter-laboratory agreement on samples of Tinnevelly senna pods.However, biological tests on the same samples gave inconsistent results, and it was not possible to use these to assess the validity of the chemical method as a means of estimating the purgative activity of the drug. The Joint Committee therefore decided to set up another Panel (3A) to examine biological methods of assaying anthraquinone drugs; pending the outcome of this new Panel’s work, chemical investigations have been discontinued.If and when a reliable biological assessment becomes available, chemical work will be resumed on the lines suggested by the Panel in a report to the Joint Committee. CONSTITUTION- PANEL 3A : BIOLOGICAL ASSAY OF ANTHRAQUINONE DRUGS K. L. Smith, M.P.S. (Chy irman) P. F. D Arcy, B.Pharm., Ph.D., M.P.S. J. W. Fairbarin, BSc., Ph.D., F.P.S., F.L.S., G. A. Stewart, B.Sc., Ph.D., A.R.I.C. Miss A. M. Parry (Secretary) Boots Pure Drug Co. Ltd. Allen 6. Hanburys Ltd. University of London (Professor of Plzarmacog- Wellcome Biological Control Laboratories F.R.I.C. nosy) TERMS OF REFERENCE-“TO study biological methods for the assay of anthraquinone drugs.” PROGRAMME OF WORK- Biological assays of powdered senna pods, made in order to attempt to correlate results obtained by chemical methods with the purgative activity of the drug, were found to be at variance in assessing the relative potencies of the samples.It was therefore decided that, before the chemical results could be interpreted in terms of biological activity, it would be necessary to establish the conditions under whicih the biological method of assay would give reproducible results. Accordingly, this Panel was set up to investigate biological methods for the assay of senna and other anthraquinone-containing drugs. PROGRESS OF WORK- of senna pods is now in progress. CONSTITUTION- The Panel held its first meeting in August, 1960, and collaborative work on the assay PANEL 4: RAUWOLFIA C. A. Johnson, B.Sc., B.Pharm., F.P.S., F.R.I.C. T. Davies, BSc., A.R.I.C.Miss €3. Gartside, B.Pharm., M.P.S. J. J. Lewis, M.Sc., F.P.S. A. W. Peacock, B.Pharm., F.P.S. Miss A. M. Parry (Secretary) Boots Pure Drug Go. Ltd. CIBA Laboratories Ltd. Pharmaceutical Society of Great Britain University of Glasgow (Department of Materia Riker Laboratories Ltd. (Chairman) ’ Medica and Therapeutics)May, 19611 REPORT OF THE ANALYTICAL METHODS COMMITTEE 1960 31 1 TERMS OF REFERENCE-“TO investigate methods of assay for rauwolfia and its preparations with particular regard to the content of reserpine and related alkaloids.” PROGRESS OF WORK- and its Report was published in the October, 1960, issue of The Analyst. now been disbanded. As mentioned earlier in this Report (see p. 299) , the Panel has completed its programme The Panelhas PANEL 5 : LONCHOCARPUS AND DERRIS CONSTITUTION- R.F. Phipers, B.Sc., Ph.D. R. Buckley, BSc., A.R.I.C. J. A. Dawson, B.Sc., A.R.I.C. W. E. Drinkwater, F.R.I.C. R. V. Foster, MSc., A.R.I.C. S . C. Jolly, BSc., B.Pharm., M.P.S., A.R.I.C. J. T. Martin, D.Sc., F.R.I.C. R. A. Rabnott F. H. Tresadern Miss A. M. Parry (Secretary) (Chairman) TERMS OF REFERENCE-‘ ‘TO investigate methods Cooper Technical Bureau Plant Protection Ltd. D.S.I.R., Tropical Products Institute Boots Pure Drug Co. Ltd. Cooper Technical Bureau Pharmaceutical Society of Great Britain University of Bristol (Long Ashton Research Analytical and Consulting Chemist Stafford Allen 6. Sons Ltd. Station) of assav of derris. lonchocarpus and their preparations, with particular refereice to the determinition of their rotenon; content.” PROGRESS OF WORK- The gravimetric method for The Determination of Rotenone in Rotenone-bearing Plants with Special Reference to Lonchocarpus, published by the Panel (Autalyst, 1959, 84, 735), is not applicable to preparations having a very low rotenone content or containing interfering substances.The Panel has therefore been examining a colorimetric method that is used commercially for the control of preparations containing rotenone. This method, although empirical and not necessarily giving the true rotenone content, has been found satisfactory by individual firms. However, when it was applied to preparations in collabora- tive tests, the results were disappointing, and it was clear that more specific definition of the details of the procedure was required.The Panel is therefore using solutions of purerotenone to investigate the technique of the method and to determine the optimum conditions for the development of the colour; some progress has been made on these lines, and it is hoped that as a result a method that gives reproducible results will be recommended. PANEL 6: PYRETHRUM CONSTITUTION- W. Mitchell, BSc., Fh.D., F.R.I.C. (Chairman) H. E. Coomber, BSc. L. Donegan M. Elliott, Ph.D. A. D. Harford S. C. Jolly, BSc., B.Pharm., M.P.S., A.R.I.C. W. S. Manson, B.Sc., A.R.I.C. R. A. Rabnott F. H. Tresadern Stafford Allen & Sons Ltd. Mitchell Cotts 6. Co. Ltd. D.S.I.R., Tropical Products Institute Rothamsted Experimental Station British Petroleum Research Centre Pharmaceutical Society of Great Britain Cooper Technical Bureau Analytical and Consulting Chemist Stafford Allen G.Sons Ltd. T. F. West, Ph.D., DSc., A.M.I.Chem.E., A f&an Pyrethrum Technical I n formation Centre F. R. I.C. Ltd. Miss A. M. Parry (Secretary) TERMS OF REFERENCE-“TO investigate methods of assay of pyrethrum flowers and pyrethrum extract with a view to recommending a standard chemical or physical method of assay.” PROGRESS OF WORK- For many years difficulties have been experienced in trading in pyrethrum owing to the variations in results of analyses from different laboratories ostensibly using the same or similar methods of assay; despite collaborative trials on an international scale , these difficulties have remained unresolved. In view of the obvious need for a reliable method of assay for pyrethrum, the Joint Committee decided to set up a Panel to investigate the problem.312 REPORT OF THE ANALYTICAL METHODS COMMITTEE 1960 [Vol. 86 The Panel began work at the beginning of 1960 and, after reviewing the various types of chemical and physical methods that have been published for the assay of pyrethrum, selected for detailed study a mercury-reduction method, variants of which are most widely used in commerce.It was thought that, since reproducible results could be obtained within individual laboratories, the inter-laboratory discrepancies might arise from differences in technique or quality of reagents; accordingly, the method was drafted in precise detail and tested by seven laboratories, all using portions of the same samples of extract.The inter- laboratory agreement between these laboratories, two of which are in Kenya, was most encouraging. Work is now in progress to try to establish the critical features of the procedure that may have been responsible for past divergencies in results and to define the techniques that will give the most reproducible results. The Panel has so far been concerned with extracts of the drug, but intends to extend its work to include the assay of flowers of pyrethrum. 1959 L L 31 4 3140 115 266 23 65 21 119 4063 - 107 1292 APPENDIX I THE SOCIETY FOR ANALYTICAL CHEMISTRY ANALYTICAL METHODS TRUST ACCOUNTS FOR THE YEAR EN:DED OCTOBER 3 1 s ~ , 1960 Income and Expenditure Account for thts Year Ended October 31st, 1960 L5462 - 1959 t 14,086 L14,086 - A d Rent, Light, Heat and TeleDhone .... 246 Salari& . . .. .. 3497 Office Equipment . . 46 Printing and Stationery 138 Travelling Expenses . . 23 Expenses of Meetings . . 136 Audit Fee and Accoun- Postage and Petty Ex- - 4229 Scholarship Grants and Awards for Research 200 Contribution to Decora- tions and Fittings of Council Room .. 148 Excess of Income over Expenditure for the year ended October 31st, 1960, transferred to Accumulated Fund 1706 L6283 tancy . . .. .. 42* penses . . .. .. 101 - Balance 11959 L € d 4857 Subscriptions from Industry. . 4461 Income Tax recovered on Covenanted Subscriptions for the years 1954-65 to - 1958-59 .. .. .. 955 Interest from Investments - 6416 360 Bank Deposit interest‘ . . . 621 10 (gross) .. 10 Sales of “Recommended Meth- ods for the Analysis of Trade Effluents,” received from Society for Analytical Chem- 235 instry .. .. .. 336 Accumulated Fund 1 1959 il; carried to Balance Sheet 16,831 L15,831 I I L6283 il; ;G 2,794 Balance a t October 31st, 1959 . . 14,086 Increase in value on Redemption of &lo0 Government of Ceylon Excess of Income over Expendi- ture for the year ended October 1292 31st, 1960 - .. .. .. 1706 4,086 k15,831 - 3&y0 Stock, 1959 . . . . 39 - - * Including fee for recovering Income Tax on Covenanted Subscriptions.1959 L L 14,086 Accumulated Fund . . . . 15,831 3264 Sundvy Creditors . . . . . . 2728 ,(17,350 1959 L Investments (at Cost) : LlOO Government of Ceylon 34% Stock, 1959 (redeemed 61 15.12.59) 4100 34% convey- 83 sion Stock 83 100 ~100 3&% war stock 100 (Market Value at 31.10.60, Q21) 22 Sundry Debtors . . 4 4 - 244 - Cash: At Bank on- 9000 Deposit Account 11,000 8084 Current Account 7340 17,084 - 418,669 L17,350 - - -I 313 il 183 36 - 18,340 i18.669 - Signed on behalf of the Analytical Methods Trust Fund G. H. LLOYD- JACOB, Chairman, J. HUBERT HAMENCE, Honorary Treasurer. Report of the Auditors to the Trustees of The Society for Analytical Chemistry Analytical Methods Trust Fund We have examined the above Balance Sheet which in our opinion gives a true and fair view of the state of affairs of the Trust at 31st October, 1960. 10 New Court, Lincoln’s Inn, LONDON, W.C.2. 6th February, 1961. (Signed) RIDLEY, HESLOP & SAINER Chartered Accountants, Auditors. APPENDIX I1 SUBSCRIBERS TO THE TRUST FUND DURING 1960 Albright & Wilson Ltd. The Associated Ethyl Co. Ltd. Boots Pure Drug Co. Ltd. The British Aluminium Co. Ltd. The British Drug Houses Ltd. British Glues & Chemicals Ltd. British Oxygen Research & Development Ltd. Brotherton & Co. Ltd. Central Electricity Generating Board The Distillers Co. Ltd. Dunlop Research Centre Esso Research Ltd. Glaxo Laboratories Ltd. Arthur Guinness, Son & Co. (Park Royal) Ltd. Hopkin & Williams Ltd. Horlicks Ltd. Huntley & Palmers Ltd. Imperial Chemical Industries Ltd. Laporte Chemicals Ltd. J. Lyons & Co. Ltd. Macfarlane, Lang & Co. Ltd. May & Baker Ltd. The Metal Box Co. Ltd. The Millers’ Mutual Association Procea Products Ltd. Quaker Oats Ltd. Rowntree & Co. Ltd. “Shell” Research Ltd. John & E. Sturge Ltd. Unilever Ltd. Vitamins Ltd. Weston Research Laboratories Ltd.

ISSN:0003-2654    

DOI:10.1039/AN9618600297

出版商:RSC    

年代:1961

数据来源: RSC

摘要:

314 ADDRESS OF THE RETIRING PRESIDENT p o l . 86 Address of the Retiring President R. C. CHIRNSIDE, F.R.I.C. (Delivered after the Annual Gevteral Meeting, March 3rd, 1961) The Enlargement of Horizonsl in Analytical Chemistry IT has been my privilege during the past 33 years to have listened to every Presidential Address to this Society, starting with that of E.. R. Bolton in 1928. Bolton opened his address to what he termed “our little Society,” with its 580 members, with the following words- “The report I have to make to you this evening upon the activities of the past year is a happy story of unprecedented progress, unpunctuated by any very startling events . ” I hope that you will not be disappointed or too greatly alarmed when I say that 33 years later, and after a total of 16 years of service on Council, I do not feel quite so confident as Bolton about the state of our health.I shall not attempt to burden you with an account of my stewardship over the last 2 years-instead I want to invite you first to look a good deal further back over the history of our Society. It was nearly 50 years ago, in 1912 to be exact, when E. W. Voelcker, the father of our good friend Eric Voelcker, introduced the new President, Leonard Archbutt, Chief Chemist of the Midland Railway, in the following terms-- “Mr. Archbutt has the distinction of being the first President of this Society who has never held the post of Public Analyst arid I think it was a very happy suggestion that the gradual enlargement of our horizons-which a few years ago resulted in our incorporation as a Society which embraced all branches of the analytical profession- should now be marked by the election of Mr.Archbutt as President.” May I draw your attention to the phrase from which, like the Scottish preacher, I take my text-“the enlargement of our horizons.” By 1913 we find Archbutt himself saying- “I think we ought to have a much larger membership.” “I am afraid the amplification of our titlle in 1905 to the Society of Public Analysts and Other Analytical Chemists has not entirely removed the misconception that we are essentially a Society of Public Analysts.” A few years later, in 1919, Samuel Rideal, the father of Sir Eric Rideal, was President, and he too had something to say about the name- “I am not certain,” he said, “whether we might not consider shortening the long name of our Society to that of the Society of Analysts and thus bring our title in accord with that of our Journal.” I mention this because Rideal’s comment suggests that by 1919 our Journal, The Analyst, was thought to be reflecting the gradual enlargement of the Society’s horizons. We now have just on 2000 members, and the misconception to which Archbutt referred as long ago as 1913 is, I hope, dispelled.We have not shortened our name as Rideal suggested, but have changed it, though only after another ‘“40 years on.” It might be argued that the “gradual enlargement” to which Voelcker referred has indeed been gradual, perhaps too gradual. It was certainly a surprise to me to discover, for example, that in the last 50 years the Society has only twice gone outside the rather narrower field of its earlier interests for its President.On the other hand, our journal, The Analyst, now has a circulation of nearly 7000, has had several “new looks” and may yet have more. Analytical Abstracts, with an even larger circulation, begun in 1954, has already established itself not only in this country but also in some European countries, Scandinavia and the Netherlands, for example, and also in the United States of America. and again-May, 19611 ADDRESS OF THE RETIRING PRESIDENT 315 It has always seemed to me that a learned Society, and we may lay claim since our change of name to be one, stands to be judged primarily by its publications and by its meetings. I have already touched on publications in passing, and I shall have something more to say about them and about meetings in due course. Suffice it to say that much of our thinking has of late gone into both and both continue to be the object of further study.Why, then, in the face of our achievements, do I not radiate satisfaction and optimism like Bolton? It may need greater discernment than I can hope to bring to the task to give you a simple and concise answer. My main doubt, as I see it, arises from an awareness that, while the Society of recent years has been catching up, analytical chemistry itself has not been standing still. So much so that he would be a brave man who would to-day attempt a proper definition of analytical chemistry or chemical analysis, or indeed a description of the analyst himself.On reflection, however, I did not think this should deter me from trying to put before you at least some aspects of the situation as I see it. The laying down of the seal of office brings with it, I trust, certain freedoms, and possibly a unique opportunity, and a responsibility, to speak -and if necessary to speak out-on the things that seem of greatest import. Those of us who were born near the beginning of the century can, I think, count ourselves privileged to have lived through such exciting times. In a span of little more than my own lifetime science has grown from an academic pursuit to become an integral part of the back- ground of much of modern industry. Although we must all look with mixed feelings at the undeniable fact that two wars have accelerated this process, it would seem that nothing short of such a crisis can render palatable new ideas, and not only new ideas in chemistry, to naturally conservative minds.When I entered chemistry just after the end of World War I, few industrial concerns had begun to think really scientifically. They did not in many instances have laboratories of their own-this was true even of some of our basic industries, the coal industry, for example. They certainly did not have research laboratories, for these were not yet fashionable. Analysis as I remember it would in the main have been more properly described as assaying. Analytical determinations were made so as to be able to assess the commercial value of a material. It might, for example, be a determination of the iron or manganese content of an ore, the sulphur content of pyrites, the available chlorine in bleaching powder, the “proximate” analysis and the calorific value of coal.Another requirement of analysis was to check conformity with a standard or a specification. Metals and alloys were subject to specifications of com- position and of levels of impurity which, it was fondly believed, could be transmuted by mathematical skill into a satisfying description of mechanical properties. Other materials might have to comply with regulations: mine dusts and mine airs with safety regulations; foods and drugs to certain legal standards or to those established by custom. I well remember on Tyneside how even the grease that was to be used during the launching of a ship had to be tested shortly before the event, and one of my nightmares, when I had been so engaged, was to wonder whether the great ship would slide smoothly into the water the next day or whether, because of some error of mine, the whole ceremony would end in disaster.Some parts of industry had, it is true, set up analytical laboratories as a first and a laudable effort to introduce science into industry. It was believed, with some justification, that a measure of control in manufacture would result from the analytical information provided about chemical composition or the nature and amount of impurities in raw materials, or in the finished product. The steel industry, for example, has a better record than most in this respect, and I have never ceased to admire the skill and the speed of their “shift” chemists.Nevertheless, when I first began work in a laboratory, analysts as a whole were in the depressed classes of the chemical community; to be fair, let us add, at a time when there was much depression about. The whole atmosphere of this period is reflected in the closing words of G. Rudd Thompson’s address in 1925; they were enough to deter any young man from entering the profession- “I appeal therefore,” he said, “to those already engaged in analytical chemistry and especially teachers of chemistry to discourage all students who contemplate chemistry as a profession other than that minority who show an exceptional aptitude for this type of work and who are in addition convinced that the satisfaction of chemistry for its own sake can outweigh the very limited prospect of material success which now obtains.316 ADDRESS OF THE RETlRING PRESIDENT [Vol.86 “The older I get,” he went on to say, “the more sympathetic and possibly more pessimistic do I become in regard to this question of the failure of recognition of merit and knowledge acquired after many years of hard work and honest intention. As a Society, as a Council, as individual members, we can do very little to remedy this for we are all more or less in the same boat. A change for the better may come and probably will come in time but how is not for me to suggest nor do I see a means of improvement other than that mentioned. ” That was in 1925. My span of professional life has extended over two social extremes; this period of depression in the twenties to thle present day, when the analyst begins to have a scarcity value.I was fortunate not very long after the time of Rudd Thompson’s depressing prophecy to find myself in the environment of industrial research, in a pioneer research laboratory. Its work was directed to the scientific and technological problems of a large Company, a Company that was in itself really a collection of industries, ranging from the very old, founded on the arts, like glass and ceramics, to the very new, founded on and derived from basic scientific developments. This was the context in which I was called upon to provide a professional analytical service. It began to be clear before long that even in those days I had to do some new thinking about analysis and its place in the scheme of things.I came soon to realise that a con- ception of analysis restricted to a statement of percentage composition, expressed in the arbitrary way that I had come to accept, was often inadequate, and sometimes useless. I learned, too, that even scientists and engineers often did not know the right question to ask of the analyst and almost as often did not fully appreciate or understand the answers they were likely to get from him. There have been many more lessons to learn since that time during the formative years of a group whose primary objective has been to give scientific service to a number of research groups and also to works engineers and technologists. Over so long a period and with such a variety of interests to cover, I have not unnatiirally developed a philosophy about analysis and its purpose, and I venture to think that it comprises some matters of sufficiently general concern to be of interest to you here to-day.Sooner or later the research worker engaged on any problem in which materials are involved will require certain basic measurements. You will remember Lord Kelvin’s classic dictum- “When you can measure what you are speaking about and express it in numbers, you know something about it ; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind.’’ All analysis ends in measurement, and measurement is a physical process. If this were better remembered or better understood I think: there would be less extravagant talk about physical methods of analysis.Your research worker often finds that his academic training and his experience do not enable him to make these measurements. He may therefore have to choose one of two courses -either to step aside and spend his time in becoming a quasi-expert, or, because this process may have to be repeated many times and because it takes a deal of time to become expert, to go instead for help to a professional service l;roup where they are not only expert in the measurement, but where nowadays the necessary and often extremely expensive equipment for that measurement exists. At first sight, the second of these choices would seem to be the more profitable, but this is to oversimplify a problem which is often not even diagnosed, and where it is, is by no means completely solved.If for the moment you will accept the term “analysis” to cover what I have referred to as “measurements,” although these seldom have any intrinsic value, taken singly or together they often serve to indicate the potentialities of some substance or material. If you were to ask what do I mean by analysis, and if I were to be allowed to exclude assaying or testing, I could find no more apposite definition than that given some years ago by one of our Past Presidents, E. B. Hughes. He defined analysis as “the examination of a material to ascertain its composition, its properties, its qualities,” and I want to suggest to you that the greatest of these i s no longer necessarily composition. In my opinion it is just because the term analysis has for so long been interpreted to mean only compositionMay, 19611 ADDRESS OF THE RETIRING PRESIDENT 317 that so much useless analysis has been and is being carried out, that so many of those who wanted information about the properties or the qualities of a material have been discouraged and are confirmed in their view that the analyst is a poor fellow and that he is giving them an inadequate and sometimes an out-of-date service.I t is in these circumstances that the scientific worker may be tempted to make the first of the choices to which I referred; he will try to get the information he needs himself and, what is more, he will not restrict himself to the use of the tools and techniques that the analyst has been accustomed to think of as his own.Trained though I was as an analyst, I have never been able to share the complaints and protests of the analyst that such a situation seems to engender-indeed, I incline to the view that most of the advances in analytical techniques and tools in the last 20 revolutionary years have come, not from analysts, but from those whom the analyst might in one sense be said to have failed. Some of the most revolutionary and exciting have come from the biochemist, to whom we all owe a great debt ; consciously or unconsciously, these developments have arisen because the analyst so often has not been able to give the biochemist or the research worker in some other field the kind of information or measurement he required. I need mention only gas chromato- graphy to illustrate my point.In my own laboratory we had to learn that ourfunction at timeswas to resemblethat of the physician, and that we had to use our knowledge, our senses and our skills to diagnose, and to help in prescribing remedies for industrial ills. This implied a responsibility and a willingness on the part of the analyst so to enlarge his own field of knowledge as to be able to comprehend the nature of his customers’ problems. How otherwise would he be able to scrutinise critically analytical requests, to ensure that they were properly stated, that they were likely to furnish useful information and that their cost would not be wholly incommensurate with their probable value? I was fortunate to come into contact early in my professional life with sympathetic physicist colleagues, sympathetic, that is, to the philosophy I have been trying to outline.The physicist was himself a newcomer to industry, and he brought with him some new thinking-and some sorely needed new thinking-from which the analyst could not fail to profit. When we began to consider what tools and techniques we had available among us, and what kinds of information we could obtain by an intelligent selection from, or combination of, these various techniques, the possibilities seemed unlimited. It became evident at once that we had to think of a newer and wider conception of the science and the craft that we used to call analytical chemistry and, also, of the person whom we used to call an analytical chemist. You will, I think, agree at once that to accept the wider conception of analysis that I am suggesting involves a drastic revision of our thinking.The place of the analyst himself may sometimes be taken by a team of specialists, some of whom would formerly have had no place in the traditional analytical laboratory. The professional analyst was always some- thing of a specialist among chemists; he is now often a specialist and not always a chemist among analysts. I would differentiate, very sharply, analysis from assaying; the determination of the composition of a substance, an important and often enough a difficult matter calling for the highest skill, may nevertheless frequently give only the minimum information required. But it is not only techniques of analysis that change: it is also the kind of information they give.There can be no static or permanent conception of what constitutes analytical information. This, too, must change as our understanding grows, particularly our knowledge of the solid state. Some of the latest instrumental techniques enable us to get conventional information in a very much shorter time, and their principal application is therefore to testing. I may add that the achievements in this direction, particularly with automatic, direct-reading spectroscopy, are nothing short of sensational. But I am more concerned to bring to your notice the new kind of information that instrumental and other new techniques make it possible to obtain. I have in mind identi- fication of compounds, or phases, or solid-solution effects, the distinguishing between poly- morphic forms of a substance, information on fundamental crystal size and crystal shape, on lattice strain, on inhomogeneity, on inclusions, on differences in surface and body composi- tion, on the nature and amount of impurity at levels in the parts per million, ten million or a hundred million range, on the nature and amount of gases dissolved in solids. All this and more, in my experience, is becoming vital to the study of the behaviour and uses of materials.318 ADDRESS OF THE RETIRING PRESIDENT [Vol. 86 I could give examples from my own experience of materials that, on the basis of every conventional chemical method of examination, appear to be identical, yet behave quite differently in some modern.app1ication.Two that spring to mind a t once, it may surprise you, are the “simple” compounds ferric oxide, Fe,O,, and aluminium oxide, A1,0,.Gray and Bacharachl have drawn attention recently to some of the equally pressing and more vital analogous problems in biochemistry, “where there is often a need to distinguish between substances for which there do not exist, and possibly never can exist, differential chemical tests.” “Nowhere,” they say, “has the need for meticulous separation, sometimes on a millimicrogram scale, of closely related compounds been more urgently felt or more diligently sought than in the field of . . . biochemical analysis.” Some of the problems that arise in the analys’is of food provide perhaps the best examples of the inadequacy of our present knowledge. IDr. Hamence rightly drew attention in his address 2 years ago to the need for techniques for the separation and determination of natural substances when they are present in a mixture, in contrast to the indirect methods of assessment on which much of our present work has to be based.In this context one has only to think of the arbitrary calculation of “protein” content from a figure for nitrogen, itself derived from an actual determination of ammonia. This is an occasion when, with some regret, I must resist the temptation to talk in particular about the potentialities and the applications of any one of the modern techniques, chemical, physical or instrumental. I have in any case already given many concrete examples of their use and application in my papers to the Congress on Modern Analytical Chemistry in Industry at St.Andrews in 1957 and to the International Symposium on Microchemistry at Birmingham in 1958. The analytical revolution of which everyone has become so conscious during the last 15 to 20 years began with us many years earliler when, as I have already mentioned, we invited the help of the physicist in attempting a more novel approach to some of the problems that arose in our own laboratories. This new situation is not without its dangers; indeed, they are already evident. Despite the wonderful new techniques that have been put into our hands, we may merely succeed in amassing many more analytical results in a much shorter time. So far as it goes this may well offer a solution to the vital requirement of speed in many testing laboratories, but it may sometimes be prudent to ask if the results are really necessary. The enthusiasts for many of the modern techniques are in danger of spreading the thought that instrumental techniques render superfluous the classical analyst. This :is not yet true; indeed, we are already in difficulties because he is so scarce.It is true, however, that in some applications of modern instrumental techniques it is not only the analyst but also the analytical laboi-atory that is rendered superfluous, for with these techniques some qualities of a material in a chemical plant can be continuously monitored and effective automatic control of the process established-the true meaning of automation. The term “instrumentation” is often enough that used in connection with the measure- ment of some physical quality other than mass or volume, and we need to remind ourselves sometimes that the chemical balance is a physical instrument.It is of the greatest im- portance that we use the newer techniques to supplement, or to complement, as well as to replace, classical analytical methods in the measurement of the things that matter, to obtain information that offers the greatest possibility of translation into a useful and satisfying statement of properties of a material, be they mechanical, electrical, biochemical, nutritional, or what you will. In short, we shoiild move away from the nineteenth-century idea that analysis is wholly concerned with a statement of composition and that this, in the inorganic field at least, can be set down as a list of arbitrarily defined oxides or radicals.I would hope also that, as another consequence of the acceptance of such a philosophy, the dis- tinction, hitherto often obscured, between testing and analysis might become more clear. Seen in retrospect, the golden age of analysis in the last century, to which so many nostalgic references have been made by my predecessors, and the lowering of the status of the analyst in the earlier half of this century are understandable. The present structure of chemistry, geology, mineralogy and some other :sciences was built up on analysis: the com- position of much that goes to make up our material world was charted and a vast collection of basic information was established. In mineralogy alone the analyst and the microscopist carried out a herculean task.Much of the work was truly heroic, and it was directed to scientific ends. When, later, the emphasis shifted to the commercial control of materials There is, however, a greater hazard.May, 19611 ADDRESS OF THE RETIRING PRESIDENT 319 by analysis or test, to fix a price, to meet a specification, to comply with a regulation-when, in other words, the objective seemed no longer to be so unambiguously scientific-then the status of analysis fell and that of the analyst with it. We are probably all confident that the status of analysis has now risen again. Can we be quite so confident about the status of the analyst? Paradoxically, I am inclined to think that we cannot, perhaps because it is no longer so easy to identify the analyst.The “tester,” of course, presents no such difficulty: “he” is now often “she” or “it,” “she,” a girl, not necessarily a qualified chemist but having a high degree of skill and intelligence; “it,” an instrument, sometimes large, often expensive. A great deal of what I would regard as true analytical work is now carried out by chemists or physicists who do not consider themselves to be analysts and would describe their work by some name other than analysis. Only a minority of these people may think it appropriate to join the Society for Analytical Chemistry, and I suggest that we cannot begin too early to ask ourselves why this is so. Does the fault lie with the chemist or the physicist, does it lie with the Society, is there indeed a fault, or are we witnessing a change that is in the natural order of things? These are questions to which I suggest an answer must be sought in the next 10 years.You have only to look back at the dramatic develop- ments of the last 10 years to appreciate the force of my argument. What has it been doing these 30 years? Perhaps the first stirring from the mood of self-satisfaction reflected by Bolton was towards the end of the war, in late 1944, when the Society, in an effort to meet the changing situation, formed Groups-first the Microchemistry Group and then the Physical Methods and the Biological Methods Groups. May I just quote you two or three sentences from my Chairman’s address on the foundation of the Physical Methods Group.2 I said- “Although analysis has made great and essential contributions to all branches of chemistry, there has been a long interval in which it has remained a neglected branch of the science but there are welcome signs of renewed interest in analytical chemistry and in the analyst himself.” “This Society, whose main object as laid down in the Memorandum of Association is to encourage, assist and extend the knowledge and study of analytical chemistry, in forming Groups to deal first with microchemistry, and to-day, with physical methods of analysis, has in my view, given impetus to some sort of movement towards a renaissance in analytical chemistry.It is clear that the activities of such a Group will be concerned with some of the newer tools and techniques by which we may add to our knowledge about the composition, properties and qualities of materials either in or outside the normally accepted problems of analysis.” I think it will be agreed by all that these Groups have done magnificent work, that they have brought to the Society a new breadth of outlook.Indeed, I sometimes wonder whether they have not already accomplished the task they set out to do and whether some re-fusion or coalescence of interest is not now both possible and desirable, for we are frequently faced with the dilemma that a technique is both “physical” and “microchemical” and that it belongs to both Groups, and why not therefore to the Society? What is much more disturbing to my mind is the whole range of measurements that do not lie specifically without our province. From the first, the Physical Methods Group could provide a platform for only a limited number of techniques in a given period of time.The policy during its early life was frankly educative; after that the changes were rung as often as might be on the newer techniques-of polarography, chromatography, and the like. We once had a Polarographic Discussion Panel and, by what I now believe to be an error of judgment, we disbanded it, only to find its place taken by the Polarographic Society. But the whole issue is now becoming more complex, for analysis now rests on a number of disciplines. Under the auspices of the Institute of Physics, for example, there is an Applied Spectro- scopy Group, an Electron Microscopy Group, an X-ray Analysis Group, a Non-destructive Testing Group. There are, operating as “free radicals,” the Polarographic Society, to which I have already drawn attention, the Photoelectric Spectrometry Group and the Infra-red Discussion Group.Under the auspices of the Institute of Petroleum there is a very special and in some ways wholly admirable organisation. This is a body, known as the Hydrocarbon How does the Society stand in relation to what I have been trying to advocate? Let me give you a picture of the present situation.320 ADDRESS OF THE RETIRING PRESIDENT [vol. 86 Research Group, born in some special circumstances during the war. This body ha! now nine members; five are oil companies, one is a national board and the three others are large chemical companies. They each contribute a substantial sum of money to the Group and the Group administers these funds for the support of fundamental research in the univer sities in a number of fields-in spectroscopy, over the whole range of the electromagnetic spectrum, including, for example, nuclear magnetic resonance, in mass spectrometry, and in hydrocarbon chemistry.The Gas Chromatography Discussion Group-a body of whose enthusiasm and whose size you need no reminder, for it was with them last summer that we were able to organise such a successful Conference in Edinburgh-was formed in association with the Hydrocarbon Research Group; it was they who were quick to recognise the potentialities of the technique. I well remember how A. J. P. Martin was persuaded to demonstrate gas chromatography for the first time publicly at the International Congress of Analytical Chemistry at Oxford in 1952, and it has been a matter of some disappointment to me that this technique, developed by two of our most brilliant biochemists, should for the moment seem to have passed into other hands.It could be argued that all this was for the best, that no one Society with interests as wide as ours could have lavished so much of its energies in any one particular direction. I have no doubt at all that these various Discussion Groups have done much to speed up the development of their respective techniques’ and that we have all benefited as a conse- quence and owe them a debt. Nevertheless, I do not think we could claim that this factor was uppermost in our minds at the time; rather do I think that there was a lack of immediate realisation of the significance of some of these new techniques.Our Physical Methods Group has now devised a new mechanism to enable it to keep in direct touch with developments. It has set up advisory panels for each of the new techniques and will hope to provide a platform for a meeting on any of these topics at the appropriate time. All this is not without influence on our publications. In the first instance the coverage required in our Abstracts is very wide. We can also, I think, look not without some pride at our journal, The Analyst, transformed out of all recognition since I first had a sight of it in 1922. But the multiplicity of Societies to which I have referred is reflected in an almost equally long list of specialist analytical journals-the Journals of Chromatography, of Polaro- graphy, of Electroanalytical Chemistry, etc., not to mention at least one other British and one European journal covering the field of general analytical chemistry.Apart from any other aspects, it is clear that the subject of analytical chemistry is now among the “best sellers.” A learned Society starts with something of a handicap com- pared with a commercial publishing house, but again, I would think this a cause neither for complaint nor for complacency, and much thought is being given at the moment to future developments in our journal. Review papers and monographs are among the other contem- porary developments. I would mention, moreover, that on the cover of The Analyst its objectives are set out clearly for all to read-“a publication dealing with all branches of analytical chemistry”-and there is no reason why this should not be as comprehensive as possible.During this last year the proceedings of the two major symposia, which we have helped to organise, have been published in two handsome books-“Gases in Metals” and “The Third Gas Chromatography Symposium”--in both of which we cover many of the techniques of the modern investigator. These are revolutionary times and even a scientific society cannot expect to escape the wind of change. It cannot and should not assume that, on the first Wednesday of every month at seven in the evening, a large number of its members will continue to choose to listen to three papers on three diverse problems in analysis just because they have done so in the past, and in preference to the counter-attractions that are now available within or without their homes. It is already evident that we were wise, 2 or 3 years ago, to set up a Programmes Committee and that they in their turn have been wise to fizshion a new pattern of meeting.I would like to refer in more detail to some aspects of the meetings that the Society has held jointly during this last year, first with the Fertiliser Society, then with the two metallurgical institutions-the Iron and Steel Institute and the Institute of Metals-on the determination of Gases in Metals, and later with the Gas Chromatography Discussion Group. The 2-day meeting with the metallurgical institutions, for example, attracted over 300 people, including a number of distinguished workers from the United States of America and from What about our meetings, the other main responsibility of the Society?May, 19611 ADDRESS OF THE RETIRING PRESIDENT 321 the continent of Europe.Among the techniques discussed were vacuum fusion, emission spectroscopy, isotope dilution, X-ray emission and even the measurement of internal friction. Close on 600 people, 160 of them from overseas, came to the 4-day meeting in Edinburgh on Gas Chromatography. These events serve to illustrate a changing pattern of scientific meeting, which we have done well to recognise. But they illustrate something else that we also have to recognise; that not more than about one third of those attending such meetings are members of this Society. For some, the reasons are obvious and valid, but of the others, many, I would suggest, belong to that section of chemical society to which I have already made reference: they do not admit to the practice of analysis and they reject the label of “analyst.” In pointing out these problems I am offering no ready solution, but it is part of my thesis to suggest that we shall have to enlarge our horizons-that we shall have to face up to the diversity of disciplines now involved in what used to be called analytical chemistry.“Like it or not,” says Liebhafsky in the preface to his recent book on “Spectrochemical Analysis with x-ray^,"^ “the chemistry is going out of analytical chemistry. For a long time indeed, Chaucer with his ‘The lyf so short, the craft so long to lerne Th’ assay so hard, so sharp the conquering’ proved a better prophet than he knew.But nowadays physics and electronics are in part being fused with analytical chemistry to make the assay easier and the conquering less painful.” . In passing, we should note the dependence of pure science on technology-to which G. P. Thomson4 has recently drawn our attention-both the material return and also in the realm of ideas. A modern laboratory could not work without the instruments developed for technology and obtainable more cheaply because industry has required them to be made in reasonably large numbers, I referred earlier to the many other groups that are concerned with the techniques of measurement, measurements which, I submit, are, or sooner or later will be, thought to constitute analytical data.Some of these groups, for example, the Applied Spectroscopy Group or the X-ray Analysis Group of the Institute of Physics, are firmly attached to other learned Societies ; some, like the Gas Chromatography Discussion Group, are more loosely attached to other bodies; some others have no such affinities and one associates them mainly with the fields of work, say biochemistry or metallurgy, for which they were perhaps first developed or in which they were first applied. This is the crux of the matter and this is the reason why, unlike Bolton in 1928, I do not see our future as one of uneventful, steady progress. The loyalties of a11 these groups lie in the main well outside the bounds of this Society. There is at once paradoxically a gap and an overlap. Despite the efforts of the Physical Methods Group since 1945, the Society for Analytical Chemistry will, I think, have to do still more to try to bridge this gap, to accept at a faster rate the need for new kinds of measurement with new kinds of tools.Ultimately this means the acceptance of a new conception of “analysis.” There is perhaps an even greater need for the exponents of and enthusiasts for these new techniques to recognise the overlap, to accept perhaps a little more humbly that there are skills, and there is art, in classical analytical chemistry; that spectrography is not the most sensitive technique for many elements; that iron, for example, can be determined more readily, accurately, and at a lower level by chemical methods than by radioactivation methods; that classical analysis is not necessarily always more tedious or time-consuming than other methods, and that even troublesome “blanks” can be just as troublesome when they are called “signal to noise ratio.” I do see, however, an exciting and a stimulating challenge-a challenge to the analyst to establish closer contacts with those working in the newer fields of measurement-to set up some mechanism for collaboration during this period of transition from classical analytical chemistry to analysis based more broadly on other types of measurement besides those of mass and volume and on information that includes, but sometimes only as an essential minimum, a determination of composition. I have the strongest conviction on this matter, based as I said that I did not see the future as one of uneventful steady progress.322 ADDRESS OF THE RETIRING PRESIDENT [Vol.86 it is on so long an experience of the value of the co-lordination and application of many diverse analytical techniques in my own environment. I would like to touch briefly on another matter in which I feel this country rather than our Society has been dragging its feet, and I do so only because I think it has a bearing on my general theme. I refer to the establishment of University Chairs in Analytical Chemistry -for which our President, Chaston Chapman,6 put in a plea over 40 years ago. The satis- faction we must all feel that two have now been set up in Great Britain is tempered for some of us by the fact that they have come, if not too lai:e, certainly at a time when we have begun to cross new frontiers-when, as I have already mentioned, some of the chemistry is going out of analytical chemistry and when it now begins to rest on a diversity of disciplines and often looks like analytical physics. While, therefore, this revival of interest in analytical chemistry is indeed welcome, both in our Universities and in our Colleges of Advanced Technology, they too will have to face some of the problems I have been trying to delineate. I may add that already in one College of Advanced Technology the students for the Diploma of Technology in Applied Chemistry include in the third and fourth years a course in electronics and instrumentation.May I offer another thought to those in the IJniversities? It is this-I think that they would be imprudent, if not unwise, to assume that even in purely chemical matters the analyst in industry is a benighted creature, steeped in empiricism and sadly in need of theoretical enlightenment.Ostwald came near to making this mistake, as Lundell pointed out in his now famous lecture on “The Analysis of Things as They Are.”G “A system,” he said, “containing ten to twenty diverse components (can hardly be handled on a strictly scientific basis and any handling of it requires actual experience in analysis.” To this I would add that physico-chemical data, however valuable, can seldom be applied to really complex mixtures. Nor let any one, either in industry or in university, minimise the value of the good classical analyst. There is still much that he has to do and that can be accomplished only by his skill and his art and through his fund of knowledge based on long experience.H. N. Wilson emphasised this point in his lecture on “Th.e Changing Aspect of Chemical Analysis”’ when he drew attention to the fact, too often overlooked or not even understood, that so many of our instrumental techniques depend for their calibration on standards that have been accurately analysed by an expert classical analyst. As this is an occasion, perhaps a unique occasion, when I may air some personal views, may I be so bold as to mention one other matter? There has sometimes seemed to me to be a pre-occupation in University analytical cirlcles with microchemistry. I have never disguised the fact that I am in this matter a heretic.Nor have I ever been able to discover whether microchemistry is the determination of a relatively large concentration of one or more constituents of a very small sample, or the determination of a very small concentration of one or more constituents of a relatively large sample. It is unfortunate also that the term should often seem to be used in the restricted field of the determination of a few elements, carbon, hydrogen, oxygen, sulphur, fluorine, etc., in organic compounds, and of the apparatus and technique as often restricted to small pieces of glassware or porcelain. I have been concerned much over the last few years, through the development of both solid-state chemistry and of nuclear power, with the determination of fantastically small concentrations of certain elements in very small samples, and I am prepared to use an appara- tus 10 feet by 6 feet, if necessary, to determine, shall we say, 1 part per 100 million of boron in 5 milligrams of a sample of a semiconductor.This more closely accords with my ideas of microchemistry. Whatever the definition, this kind of demand is going to be made on the analyst, and here, above all, new frontiers ma;y have to be crossed. Consider, for example, the special technique ltnown as the electron microprobe; this is already in use in many establishments for research in metallurgical problems, but it is also an extraordinary new analytical tool. In 1951 Castaings published results to show that an electron microscope could be converted into a useful X-ray emission spectrograph for point-to-point exploration on a micron scale, Outstanding features of the technique were the small size of the sample, a 1-p cube or thereabouts, and the absence of pronounced adsorption and enhancement effects.Castaing gives remarkable quantitative results for copper alloys; he was able to obtain analytical information by a point-to-point exploration over these extremely small areas and to show the variation in composition of a copper - zinc alloy, for example, in a region of diffusion. This kind of information, admittedly a t the extreme of my definition of analysis, is nevertheless what the metallurgist ultimately requires.May, 19611 ADDRESS OF THE RETIRING PRESIDENT 323 This leads me to comment on another aspect of microchemistry. As our techniques become more and more sensitive and as it becomes possible to use smaller and smaller samples, there will come a time-indeed it is already with us-when the answers we obtain are not of the kind to which the customer was formerly acclimatised.In one sense we have been deluding ourselves and him all the time. For example, it is possible now to determine 1 microgram of carbon present at a very low concentration in a very small sample, let us say, of titanium. We have found by experience that we can get five results in succession differing appreciably from one another and yet be confident that our apparatus is properly and correctly measuring the amount of carbon present on each occasion. Up to now the metallurgist has been used to receiving one figure, a figure representing the average carbon content of the sample used. The analyst has been used to giving that figure with confidence, because on the size of sample he used he was able to achieve high precision and good agreement on successive samples.“The results of duplicate or triplicate determinations agree’’ has been a common enough phrase and a common enough criterion in the past in judging the merits of an analytical method. But if we accept, on a purely rational basis, that as the sample gets smaller and smaller so the chances of inhomogeneity must increase, we shall ultimately arrive, and indeed I say we have already arrived, at a point where we can no longer deceive ourselves with average values-we shall give the correct or most probable value for any particular size of sample, and it will be for the metallurgist, for example, to try to make use of this information.Were we indeed able to get this information at the moment in another context, that of semiconductors, the physicist would be only too pleased to have it, for the operation of these devices depends on just these considerations. The concentration of an acceptor or a donor impurity does vary over these extremely small distances and must do so if the devices are to work. In biology, for example, were we able to determine analytically variations in concentration of this or that element or sub- stance over small local areas of concentration, might we not possibly make a contribution to the advancement of knowledge? Is not the history of science, of which we are a part, just this-as our tools become more precise, smaller, sharper, there is revealed to us knowledge and information of which previously we had no conception? I can only state my conviction that analytical chemistry as we have known it for the last 30 years, and certainly as we have known it since 1874 when the Society began, is bound to change, quite radically.I do not think that even to-day we can continue to talk of chemical analysis and of analytical chemistry and properly identify or describe the activities with which some of us are concerned, Up to a relatively few years ago the art of analysis consisted for the most part in getting our materials chemically separated or prepared in some way so that a measurement could be made, and that measurement was usually one of mass or of volume.To-day we are often prepared to make many other kinds of measurement, often without the need for preliminary separation: we can make some of them without destruction of the sample. We are already at the point where in favourable circumstances we are able to determine the composition of a minute area of a substance by a non-destructive examination of the surface. These advances arise from two main stimuli-the advances in other technologies, notably electronics, and the need and the resolve of the researcher to obtain information different in character from that offered previously by the analyst, information more scientifically relatable to the qualities with which he is concerned. I would not like to leave you with the thought that I have deserted my faith in classical analysis or that I have no concern for the commercial or legislative needs of analytical information, including so-called standard methods. But it was my special purpose to discuss that philosophy of what, for want of a better term, we must still call analytical chemistry, which exceeds the everyday repetition of routine analysis. A short paragraph from H. V. Churchill’s addressg on the occasion of his Pittsburgh award so aptly epitomizes what I have to say that I make no excuse for quoting it- Are we sure that there are not analogies in other fields? What about the next 30 years? “At meetings such as this, there is a strong temptation to be reminiscent and to recall the days of the past. But in the field of science, whether it be pure or applied, it is always morning, the beginning of tomorrow. I t is a time when dawn stands tiptoe on the misty mountain tops. I yield to no one in my admiration of the great, the near- great, and the unnamed workers who laid the foundation and built the structure that324 ADDRESS OF THE RETIRING PRESIDENT [Vol. 86 has brought analytical chemistry to its present high estate and yet analytical chemistry today is but a promise of what is to come.” Let us then enlarge our horizons, to an extent never dreamt of by Voelcker. Let us see ourselves as part of the main stream of scientific research, for in the words of Francis Bacon- “The end of our foundation is the knowledge of causes and of the secret of things and of the enlarging of the bounds of human empire to the effecting of all things possible.” 1. 2. 3. 4. 5. 6. 7. 8. 9. REFERENCES Gray, C. H., and Bacharach, A. L., “Hormones in Blood,” Academic Press (London) Ltd., London, Chirnside, R. C., Analyst, 1945, 70, 110. Liebhafsky, H. A., Pfeiffer, H. G., Winslow, E. €I., and Zemany, P. D., “X-ray Absorption and Emission in Analytical Chemistry,” John Wiley & Sons Inc., New York and London, 1960. Thomson, Sir G. P., “The Two Aspects of Science,” Presidential Address, British Association for the Advancement of Science, Cardiff, 1960. Chapman, A. Chaston, Analyst, 1915, 40, 77. Lundell, G. E. F., I n d . Eng. Chem., Anal. Ed., 1933, 5, 221. Wilson, H. N., Analyst, 1980, 85, 640. Castaing, R., Recherche adyonuutique, 1951, No. 513, 41. Churchill, H. V., Anal. Chenz., 1950, 22, 1. 1931.

ISSN:0003-2654    

DOI:10.1039/AN9618600314

出版商:RSC    

年代:1961

数据来源: RSC

摘要:

324 ADDRESS OF THE RETIRING PRESIDENT [Vol. 86 Anniversary :Dinner IN the evening following the Annual General Meeting, a Dinner to celebrate the eighty-seventh anniversary of the Society was held, by kind permission of the Prime Warden, Wardens and Court of Assistants of the Worshipful Company of Fishmongers, at Fishmongers’ Hall, London Bridge. The members and guests, numbering 153, were received by the President, Mr. R. C. Chirnside, F.R.I.C., and Mrs. Chirnside. The President afterwards took the Chair at the Dinner. The Guests of the Society and of the President included The Lord Fleck, K.B.E., D.Sc., F.R.I.C., F.R.S. (President of the Society of Chemical Industry); E. Le Q. Herbert, B.Sc., F.H.-W.C., M.I.Chem.E., M.Inst.F., F.Inst.Pet., F.R.I.C. (President of the Royal Institute of Chemistry) and Mrs.Herbert ; Sir Harry Jephcott, M.Sc., F.P.S., F.R.I.C., Barrister-at-Law (Chairman of the Council for Scientific and Industrial Research) and Lady Jephcott; Sir Charles F. Goodeve, O.B.E., D.Sc., F.R.I.C., F.R.S. (Director of the British Iron and Steel Research Association) and Lady Goodeve; G. L. Bailey, C.B.E., M.Sc. (Director of the British Non-Ferrous Metals Research Association) and Mrs. Bailey ; 0. W. Humphreys, C.B.E., B.Sc., F.Inst.P., M.I.E.E., F.R.Ae.S. (Technical Director of The General Electric Company Ltd.) and Mrs. Humphreys; A. T. James, B.Sc., Ph.D. (Chairman of the Gas Chromatography Discussion Group of the Hydrocarbon Research Group of the Institute of Petroleum) and Mrs. James; J. H. Hamence, M.Sc., Ph.D., F.R.I.C. (President of the Association of Public Analysts) ; and F.A. Pester (representing the Worshipful Company of Fishmongers) and Mrs. Pester. The Loyal Toast was proposed by the President. Lord Fleck proposed the Toast of the Society, referring to it as one designed to further a real, live, important scientific discipline. He recalled carrying out, at the outset of his career, a complete analysis of a white bearing metal, containing tin, cadmium, bismuth, antimony and lead; a difficult and arduous task. He had also made two complete rock analyses, each taking fully 10 days. By modern rapid methods such analyses took only part of a day. As these improved methods were developed, so the responsibilities of the Society became greater. The sensitivity of modern methods was such that impurities in silicon could be determined down to He continued by paying tribute to the philosophy of analytical chemistry and the analytical mind. This philosophy had come into the British way of life in the sixteenth century-he had found some reference to analysis as early as 1590.In 1661 Boyle, whom Lord Fleck called the Patron Saint of analytical chemistry, described in “The Sceptical Chymist” analysis by distillation. Analytical chemistry also owed a great debt to the parts per million.May, 19611 ANNIVERSARY DINNER 325 town of Edinburgh and its citizen Francis Hulme, who described, hidden away in a book of experiments on bleaching, the titration of lyes-in teaspoonfuls. Analysis was the basis of all scientific work. The Society encouraged the concept of analysis and the work of the analytical mind, which was one of the most valuable assets of British industry.They were very much indebted to the Society for its example and for all it did for science and for analysis in particular. The Toast was coupled with the name of the President. Mr. Chirnside, replying, recalled that in December, at the Ramsay Dinner, he had had the privilege and pleasure of responding to the Toast of “The Chemical Industry” proposed by Sir Alexander Fleck; now he had the greater pleasure of replying to Baron Fleck of Saltcoats in the County of Ayr. On that occasion one of the other speakers had referred to the Chairmanship of I.C.I. as “a dead-end job with not much in the way of prospects.J’ An alternative more in keeping with Lord Fleck’s character was, he thought, “a part-time job allowing many other outlets for his native genius.” The way in which he had guided the Fleck Committee’s rapid action in producing its report on Coal and also his masterly report on the Fishing Industry should make the country grateful that Lord Fleck had “a part- time job.” He had spoken in warm terms of the Society and its members; it was clear from his early work on the separation of radioisotopes that he had himself been no mean analyst.He had been Chairman of a great Company that believed in analysis and had nurtured in its Divisions some of the most outstanding analysts in the country. The Billingham Division had done much to further the application of gas chromatography. They had also built analytical equipment into the plant and had achieved true automation.Mr. Chirnside referred briefly to the special meetings that had been held during the past year, first with the Iron and Steel Institute and the Institute of Metals: it gave him particular pleasure to have Sir Charles Goodeve and Mr. Bailey at this Dinner. He had, too, the pleasantest memories of Edinburgh in June at the Gas Chromatography Symposium, revived by seeing Dr. James, the Symposium Chairman, among the guests. The analyst had to try to make his contri- bution to all aspects, and his own experience in the research organisation of a great and diversified Company had shown him how wide they were. Lord Fleck was President of the Society of Chemical Industry, with whom our Society was on the most friendly terms, and on whose premises it had its head office.On retiring last year from the Chairmanship of I.C.I., Lord Fleck might well have decided on a period of relaxation, but instead he had taken on both the Presidency of S.C.I. and the Honorary Treasurership of the Royal Society. It was under- stood that he could also be seen at week-ends felling trees at Billingham. Mr. Herbert would in a few weeks be completing his 2-year term as President of the Royal Institute of Chemistry, and it was clear how wise the Institute had been in its choice in 1959. Although in its early days the Society, which was 2 years older, had shown some hostility towards the Institute, in 1899 a union of the two bodies had been proposed, and cordial relations had existed ever since, Dr.Hamence, a welcome guest as President of the Association of Public Analysts, had himself been principal host 2 years before. This looked like an example of allotropy. Sir Harry Jephcott he particu- larly welcomed, for last year he had completed 40 years’ membership of the Society and was now a life member. He recalled how, in 1915, the Society had taken part in a deputation that had urged the setting up of an organisation to encourage research, which had materialised as the Department of Scientific and Industrial Research, of which Sir Harry was Chainnan. Mr. Humphreys, Director of the General Electric Company’s Hirst Research Centre, was a physicist, and very much alive to the potentialities and requirements of analytical chemistry. The President had been particularly keen to have metallurgical interests represented, and by inviting the Directors of the relevant Research Associations the Society had as their guests Sir Charles Goodeve, President-elect of the Iron and Steel Institute, and Mr.Bailey, immediate Past President of the Institute of Metals. He was glad to have Dr. James present, as a reminder of the highly successful Symposium held last year. A special guest was Mr. Pester, Clerk to the Worshipful Company of Fishmongers, whom he asked to express to the Court of Assistants the Society’s appreciation for being allowed to dine in their beautiful Hall, for which special dispensation had been granted. Finally, he welcomed all the ladies, lending colour and gaiety to the occasion. Analysis was a basic tool in all industries. Dr. Amos proposed the Toast of The Guests. There were now over 16,000 chemists in the care of the Institute.326 GOODALL AND DAVIES : AUTOMATIC DETERMINATION OF PENICILLIN [Vol. 86 Mr. Herbert replied, saying that the association of the Society with the Royal Institute of Chemistry was so close that, as he looked at the list of guests and saw how many Fellows or Associates were present, he began to wonder if he was attending a dinner of his own Institute. Being a President, he said, meant a lot of work and a lot of fun; perhaps the greatest hazard lay in attending dinners, when a President was liable to be called upon to speak. The President concluded the proceedings by calling upon Dr. Amos, the new President, who had served the Society so well as Honorary Treasurer, and investing him with the Presi- dential Badge, wishing him a successful term of (office. Dr. Amos expressed his pleasure at the honour and presented Mr. Chirnside with a. replica of the Society’s Badge to wear as a Past President.

ISSN:0003-2654    

DOI:10.1039/AN9618600324

出版商:RSC    

年代:1961

数据来源: RSC

摘要:

326 GOODALL AND DAVIES : AUTOMATIC DETERMINATION OF PENICILLIN [Vol. 86 Automatic Determination of Penicillin in Fermentation Broth An Improved Iodimetric Assay BY R. R. GOODALL AND 130SEDA DAVIES (Imperial Chemical Industries Ltd. , Pharmaceuticals Division, A lderley Park, Macclesfeld, Cheshive) The automatic analytical method described by Ferrari, Russo-Alesi and Kelly for assaying penicillin fermentation broths has been modified in order to overcome certain experimental difficulties and to improve the precision. The method described in this paper requires preliminary manual dilution to bring the concentrations of the reactants (penicilloic acid and iodine) into the linear range of the recorder - calorimeter unit, in which the excess of iodine is measured as its blue complex with starch.It is convenient to include penicillinase in the diluent, so that the automatic stage is confined to iodination, mixing with starch solution and recording the optical density of the residual iodine as its blue complex. Four of these are stan- dards, and, as the assay of each broth requxes both a “blank” to determine iodine-absorbing impurities and a “test” to determine absorption of iodine after conversion by enzyme to penicilloic acid, the net average output of assays is 18 per hour. With the accompanying standards, preparations, etc., the number of samples analysed in a normal working day is 100. The standard deviation of the assay (including both “test” and “blank” iodinations) is from 2 to 2.5 per cent. ; this is similar to that of the manual titrimetric method, in which each operator can carry out 25 tests daily.The method has been in routine use for several months. Forty iodine absorptions are recorded hourly. THREE colorimetric reactions of the penicillin nucleus have been adapted for mechanisation, These are (a) the formation of a ferric - hydroxamic $acid complex, (b) conversion to penicilloic acid, which is used to reduce arsenomolybdate to a blue colour and (c) conversion to penicilloic acid and then reaction with iodine. An automatic adaptation of method (a) has recently been described by Niedennayer, Russo-Alesi, Lendzian and Kelly.l A possible disadvantage of this method is its low intrinsic sensitivity, so that the effect of turbidity present in the sample of broth or arising during the reaction cannot be minimised by dilution ; further, under certain conditions of fennenta- tion the “blanks” for broths are of the same order as the “potencies,” with consequent loss of precision.This criticism is less likely to apply to the iodimetric assay, as the consumption of iodine by penicilloic acid is exceptionally high (about 9 equivalents per mole). Method (b), first described by Pan,2 has been adapted by Green and Monk3 to a semi-automatic procedureMay, 19611 I N FERMENTATION BROTH: AN IMPROVED IODIMETRIC ASSAY 327 involving manually operated units for rapid dispensing, extraction, evaporation, development of colour and measurement with a recording spectrophotometer. Method (c) is the most generally accepted procedure as to specificity and precision.Penicillin broth is converted by penicillinase to penicilloic acid, which is then allowed to react with iodine under acid conditions ; allowance is made for the iodine absorption of the broth without penicillinase treatment. This method is routinely used in these laboratories without any preliminary treatment of the fermentation broth.4 A visit to the Technicon Instrument Corporation’s laboratories in New York provided the opportunity for one of us (R.R.G.) to try out the fully automatic adaptation of method (c) described by Ferrari, Russo-Alesi and Kelly5 in 1959. Subsequently, our object has been to improve the sensitivity and precision of the method to the point at which a standard deviation of from 2 to 3 per cent., together with high speed of analysis, can be expected for fermentation broths of potencies greater than 2000 units per ml.Such broths have to be tested in large numbers during a mutant-screening programme. The iodination of penicilloic acid is not stoicheiometric. Consequently, the problem of achieving the desired accuracy and precision with an automatic method (this applies equally to “blank” and “test,” as the results are calculated from the difference between them) to ensure substantial agreement with the well established manual method is probably one of the most difficult applications demanded of the AutoAnalyzer. The nature of these problems is discussed below. EXPERIMENTAL DEVELOPMENT The absorption spectrum of iodine in an excess of potassium iodide solution exhibits a maximum a t 360mp.The relationship between optical density at 360mp and concen- tration over the range 0 to 1 micro-equivalent of iodine per ml is linear and can be observed as a change in optical density (0.2 cm) of from 0 to 1.8 if a suitable spectrophotometer is used. At this wavelength, however, a Technicon colorimeter fitted with suitable filters does not respond well to changes in concentration of iodine, presumably because of the low photo- activity of selenium cells in the near-ultra-violet region. Ferrari, Russo-Alesi and Kellp measured optical densities at 420mp, at the “heel” of the absorption curve, but their pub- lished calibration graph does not cover all the available scale and also has an unfavourable slope below a concentration of 2000 units of penicillin per ml, at which the optical density approaches 0.5 (equivalent to 32 per cent.transmission), corresponding to concentrations of about 1 micro-equivalent of iodine per ml. To attain the requisite precision in an absorptiometric adaptation for penicillin broths, it was necessary to span a large part of the available scale in the determination of total iodine absorption (“test”). About one-third of this must then be deducted to allow for the iodine- absorbing impurities (“blank”). To attain optical densities of the desired order over a range of low concentrations, the colorimetric reaction must be highly sensitive. Iodine absorbs only slightly in the visible spectrum, but for this work an absorption band in the visible region is required so that the AutoAnalyzer can be used to good advantage.Of the alternative methods for determining iodine, one based on the starch - iodine complex seemed to be suitable, as the absorption spectrum of this complex is broad and has a maximum at 600mp; further, Beer’s law is obeyed for concentrations less than 1 micro-equivalent of iodine per ml. The chosen concentration of soluble starch was just sufficient to develop maximum optical density with 1 micro-equivalent of iodine per ml. Although the peak absorption of this starch - iodine complex is a t 600 mp, our available interference filters had maximum trans- mission at 526 mp; our measurements were therefore made below the maximum, and some sensitivity was lost. The absorption peak, however, is not sharp, so that the difference is not critical.The blue complex is stable, provided that high concentrations of electrolyte or acid are avoided. The level of absorption is not affected by changes in room temperature. The scale of an AutoAnalyzer recorder normally records percentage transmission ( T ) , but a “linearising” device that derives 100 x the mantissa of log(T, per cent.) and displays the result on a linear scale is also available. The chart is calibrated in equal divisions from 0 to 100, and, within the limits of linear response (about 20 to 99), the transposition to optical density (d) is (100 - %)/loo, where x is the observed reading; for our purpose d is not required. This scale is about the same length as that of a normal spectrophotometer having logarithmic calibration, but the “linearised” scale can be read more precisely in the region where a328 GOODALL AND DAVIES : AUTOMATIC DIETERMINATION OF PENICILLIN [VOl.86 logarithmic form is cramped. This facilitates the precise graphical interpolation of results with the chart reader (see “Apparatus,” p. 33111. Linearity cannot be maintained below a reading of about 20, so that, for example, the curvature shown in Fig. 1 is due to a decrease in electronic response and not to deviation from Beer’s law. Other spectrophotometric measurements on these solutions show that the linear relationship continues up to 0-25 micro- equivalent of iodine per ml. I O o o 0 5 0.10 0.15 I 0.20 0.21 Concentration of iodine (as starch complex), micro-equivalents per ml Fig. 1. Relationship between concentration of iodine and chart reading when a 626-12-27 filter and a 10-mm flow cell are used I- , 0 “ O 5 0 2 4 6 s I 10 I 1 ’ 12 ‘ 1 14 Concentration of potassium phenoxymethylpenicillin standard, pg per ml Fig.2. Relationship between concentration of penicillinase-treated potassium phenoxymeth ylpenicillin standard and chart reading when a 526-12-27 filter is used The response curve obtained from a suitable range of potassium phenoxymethylpenicillin standards treated by the method described later is shown in Fig. 2. An increase in the concentration of the penicillin diminishes the concentration of the blue complex and so produces an increase in the chart reading. The “blank” for the broth is determined by usingMay, 19611 IN FERMENTATION BROTH : AN IMPROVED IODIMETRIC ASSAY 329 that part of the curve below a concentration of 5 pg per ml and the “test” on the linear part above this level.The curvature in the 0 to 5 pg per ml region arises in the recorder for the reason already stated. The development of an assay under these conditions required that the penicillin broth be treated with penicillinase and then diluted to a level at which the iodine consumed was less than the limit shown in Fig. 1 (0-15 micro-equivalent per ml). The use of the dialyser unit for rapid automatic dilution was not as promising as the more orthodox approach finally adopted. After an unsuccessful attempt to operate an automatic three-stage serial dilution of the sample drawn from the sampler plate into a network of pumping circuits, the system suggested by Dr.Holms of these laboratories was put into practice as a preliminary manual operation. This system consists essentially of a pair of self-levelling dilution pipettes (see “Apparatus,” p. 331) arranged in series. 0.073 inch bore Sample solution (0 t o 15 pg per ml) “ Cactus ” joint , b A C G in at 2.0 ml per minute >Air in at 2.5 ml per minute -Iodine solution (0.64 micro-equivalent per ml) in a t 2-0 mi per minute 0.073 inch bore silicone-rubber tubing 0.073 inch bore Starch - potassium iodide solution h j o i n t - t i 4 2 mg per rnl) in a t 2.0 ml per minute To colorimeter - and recorder a Mixing coils (3) Fig. 3. Flow diagram for iodimetric assay of penicillin Suitable standard solutions of phenoxymethylpenicillin were prepared and inactivated in 100-ml portions, so that a set of these could be incorporated on each sampling plate.As alkaline or enzymatic inactivation of the standards produced similar results, the former procedure was ultimately adopted to avoid enzymatic contamination of subsequent “blanks.” If the standards were inactivated with enzyme, the excess would have to be destroyed; obvious methods, such as boiling or precipitation by protein reagents, were thought to be impracticable. Inactivation of the samples by penicillinase was retained on the grounds of specificity. The mid-point of the acetate buffering range, pH 4.6, was chosen as the final pH for storing solutions before analysis; this was in order to avoid decomposition of the penicillin in the “blank,” a complication that could be expected at a lower pH and would result in spuriously high blank values.The necessity for high dilution outside the available AutoAnalyzer units prompted us to incorporate the treatment with enzyme in the dilution stage. The automatic part of the analysis was therefore confined to the iodination and complex-forming stages, There was no dialysis, so that theoretically there should not be much opportunity for background “noise” caused by inter-stage effects. As can be seen from the flow diagram (Fig. 3), 2 ml per minute of diluted sample are mixed with 2 ml per minute of iodine solution (0.64 micro-equivalent per ml), segmented‘ with 5 ml per minute of air and allowed to react for 2 minutes; no increase in absorption of iodine is obtained by prolonging the reaction. Subsequently, the injection of 2 ml per minute of starch -potassium iodide solution converts all the residual iodine to the blue complex.The fixed parts of the reaction circuit are in glass, with Tygon butt-joints between coils. In the feed- and pump-lines for sample and starch - potassium iodide solutions, Tygon tubing is used. Because of the high solubilityof iodine in Tygon, the dilute iodine solution enters via a polythene line into a silicone-rubber pump-tube; the starch - iodine complex also leaves the circuit via a polythene line.330 GOODALL AND DAVIES : AUTOMATIC DETERMINATION OF PENICILLIN [Vol. 86 In a normal AutoAnalyzer, a constant flow of the recipient stream passes from the dialyser to the colorimeter; the concentration of solute in this stream alters by diffusion through the cellophane membrane.In our apparatus, there is no separate recipient stream, and the act of sampling increases the throughput per minute of the liquid stream from 4 ml (2 ml each of iodine and starch - potassium iodide solutions) to 6 ml (2 ml each of iodine, starch - potassium iodide and sample solutions). Thus, there is a cyclical increase in flow and in dilution of the reagents by 50 per cent. during the time of sampling, which lasts for 1 minute, with 30-second intervals. The small “blank” peak when buffer is used as sample is a measure of this dilution effect, and the sharp rise at the end of the peaks (see Fig. 4) is attributed to the change in flow rate; this rise can be ignored. 80 70 60 50 40 30 20 10- - - - - - - - - - - - - - n i r I I/ 40 30 20 10 Fig.4. Typical recordings for penicillin broths: (a) “tests”; (b) “blanks.” Reading from right to left, the peaks in (a) are for buffer solution, thirty-three broths, buffer solution, three standards and buffer solution; those in (b) are for buffer solution, thirty-four “blanks,” buffer solution, five standards and buffer solution. (The “blanks” do not correspond to the “tests”) Several aspects of mixing become apparent when the starch - iodine complex is formed. For example, if the liquid injected into the main segmented stream is of different density, complete mixing requires passage of the segments, through approximately three loops of the mixing coil. Removal of air from the stream and passage down a capillary tube cause “drag,” so that small inter-sample boundaries become lost. Unwanted mixing and “dead” space occur at the entry to the cuvette.Precision is dependent on the absence of drift, both in the electrical components and in the concentration of iodine. To avoid drift from the components, the output of the photo- cells has to be matched and must remain so at the working temperature; this is checked by connecting the output from each photo-cell to a potentiometer and tapping off a suitable fraction to a spot galvanometer; one galvanometer is used for each photo-cell.May, 19611 IN FERMENTATION BROTH: AN IMPROVED IODIMETRIC ASSAY 331 Loss of iodine into the silicone-rubber pump-tube is greatest during the first 30 minutes; thereafter, slight loss occurs by diffusion through the wall of the tube.The effect on the assay is minimised by interpolating standards at 1-hour intervals or more frequently. METHOD APPARATUS- Compound pipettes for serial dilution-Three pipettes of the type shown in Fig. 5 are required. In operation, capillary C (bore approximately 1-3 mm; volume 0.3366 ml; length approximately 16 cm, depending on volume of joint to stopcock) is filled with sample by suction, and the outside of the jet is wiped dry. Bulb B is filled with diluent, and its contents are then used to displace and dilute the sample in C by turning the stopcocks to deliver as shown. If the volumes of bulb B, capillary C and length D are B, C and D, respectively, then the dilution factor is given by the expression [B + (C - D)]/C. After drainage, a short length of liquid, D, remains in the capillary.t Sample in Fig. 6. Compound dilution pipette To achieve a dilution of 17-5 to 1, bulb B is blown to a capacity of 5.8 & 0.1 ml and the capillary C (0-016 to 0.017 ml per cm) is made 1 cm longer than the calculated length. The operative dilution factor is determined by diluting N hydrochloric acid. A mark is made 1 cm from the tip of C, and the volume from the mark to the stopcock is filled with the acid by suction. An aliquot of the acid, after dilution as described above, is titrated with 0.1 N sodium hydroxide, nitrazine yellow being used as indicator. The ratio between the norrnalities of the acid before and after dilution is the effective dilution factor. When the desired value is attained the surplus length of capillary is removed.It is necessary to use a high-quality stopcock, such as DOVC/B/B, obtainable from G. Springham & Co., Harlow New Town, Essex. Wire racks-To contain thirty-six 6-inch x 1-inch test-tubes. Test-tubes, 6-iutch x 1-inch-Heated to 150" C, after washing, to destroy residual enzyme. Technicon A utoA nalyzer-This instrument comprises- (a) A sampling plate.332 GOODALL AND DAVIES : AUTOMATIC DETERMINATION OF PENICILLIN [Vol. 86 (b) A pump and a manifold carrying the sample line (0.073 inch i.d.), two air lines (0.081 inch id.) in parallel, an iodine line (approximately 0.073 inch id.) of silicone rubber and a starch line (0.073 inch id.) arranged as shown in Fig. 3. (c) A glass reaction circuit constructed as shown in Fig. 3. (d) A colorimeter unit having a 10-mm flow cell of modified construction such that the volume of the cuvette is decreased to 1.2 nil.The cuvette is a piece of flattened tube and does not require plane polished windows. A pair of interference filters trans- mitting in the range 520 to 600 mp is required. We use 526-12-27 filters; this code signifies maximum transmission (27 per cent.) at 526mp and a band width of 12mp at half the peak height. A recorder with a “linearised” scale. (e) Polystyrene sample cups. Chart reader-A 16-inch x 22-inch Simplon drawing-board having a movable transparent horizontal rule and two clips (obtainable from Messrs. T. Holden, Albert Square, Manchester 2). The rule is engraved, after purchase, in 1- and 0-1-inch divisions over 20 inches. REAGENTS- Iodine solution, apj5roximately 0.64 micro-equivalent per ml-Place 1200 ml of distilled water in an amber-glass bottle, add 7.7 ml of a 01.1 N solution of iodine in 2 per cent.w/v potassium iodide solution, and shake. Starch - potassium iodide solution-Add a suspension of 26.4 g of soluble starch in 200 ml of water to 1800ml of boiling water; stir during; the addition. Dispense 200-ml portions of the solution into ten 20-02 bottles, and sterilise with steam at 5 lb per sq. inch for 30 minutes. Each day, dilute 200 ml of this solution with 1 litre of distilled water, add 1.44 g of potassium iodide, and keep in an amber-glass bottle. Phosphate bufer solution, 0.5 M (PH 6.5)-Disslolve 39 g of anhydrous sodium dihydrogen orthophosphate and 35.5 g of anhydrous disodiuni hydrogen orthophosphate in water, and dilute to 1 litre.Phosphate bufler solution, 0-01 M (PH 66)-1Mute 20 ml of the 0-5 M phosphate buffer solution to 1 litre with distilled water. Penicillinase solutiort-Dissolve the contents of one vial of penicillinase (inactivation rate in 20ml is 20,000 units of penicillin G per minute; obtainable from the Distillers Co. (Biochemicals) Ltd., Speke, Liverpool) in 250 ml of the 0-01 M phosphate buffer solution. Acetate bufer solution, 0.5 M (PH 4.6)-To 500 ml of N acetic acid add 227 ml of N sodium hydroxide, and mix. Acetate bufer solution, 0.05 M (PH 4*6)-Dilute 100 ml of the 0.5 M acetate buffer solution to 1 litre. Standard phenoxymet~yl~enicillin solutions-Prepare a standard solution containing 50 mg of potassium penicillin V in 500ml of distilled water; this solution can be kept for 1 week at 5” C.Each day, prepare standards containing 2, 3, 4, 5, 10 and 15 pg of penicilloic acid per ml as follows. By pipette, place accurately measured 2-, 3-, 4-, 5-, 10- and 15-ml portions of the solution in separate 100-ml calibrated flasks, hydrolyse by adding 3.0 ml of N sodium hydroxide to the contents of each flask, and, after 10 minutes, adjust the pH of each solution to approximately 4.6 by adding 6.0ml of N acetic acid. Dilute the contents of each flask to the mark. Mix equal volumes of the solutions containing 10 and 15 pg per ml to provide a standard containing 12.5 pg per ml. These solutions comprise the penicilloic acid standards. ESTABLISHMENT OF BASE LINE- Begin to pump the iodine and starch solutions, switch on the colorimeter, recorder and chart-drive, and record for about 30 minutes with the sample line empty before beginning the determinations.(The chart reading should be within the limits 6 to 8; if it is not, suitably adjust the concentration of the iodine solution.) PREPARATION OF “TESTS” AND “BLANKS”- “BZanks”-Use one of the compound dilution pipettes to take a sample of the broth and to dilute it with 0.01 M phosphate buffer solution; shake the tube used to receive theMay, 19611 I N FERMENTATION BROTH: AN IMPROVED IODIMETRIC ASSAY 333 diluted solution. Use another compound dilution pipette (A) to sample this solution and to dilute it with 0.05 M acetate buffer solution. Each “blank” so prepared by two serial dilutions is now ready for loading on to the sample plate.Fill the plate with “blanks” as follows. Rinse a polystyrene cup with the diluted sample, fill the cup, insert it in the plate, and suitably mark the aluminium surface beside each sample with washable coloured pencil or ink. Load the plate in this order: buffer solution, standard solutions containing 2, 3, 4 and 5 pg of penicilloic acid per ml, thirty “blanks,” buffer solution and, finally, the four standard solutions. Remove the feed tube from the cuvette, flush the cuvette with water, and check that the recorder reads 100; if it does not, adjust the “100 per cent. T” potentiometer. Replace the feed tube, insert the polythene sampling tube through the crook, and throw the sampling switch to ON.^' Prepare as many plates of “blanks” as are required for the day, and record all of them before the “tests” (see below).While the plates of “blanks” are running, at the rate of forty per hour, prepare the “tests” as described below. “Tests”-Use the third compound dilution pipette to take a sample of broth and to dilute it with the penicillinase solution, shake the receiving tube, and set it aside for a t least 30 minutes. Then use pipette A to sample this solution and to dilute it with 0.05 M acetate buffer solution as before. Load the samples and standards on a plate in this order: buffer solution, standard solutions containing 5, 10, 12.5 and 15 pg of penicilloic acid per ml, “tests,” buffer solution and, finally, the four standard solutions. (Omit the first set of standards on subsequent plates.) When the “blank” recordings are complete, remove the plate, and replace it with the plate carrying the “tests.” Check the “100 per cent.T” setting as before, and begin to sample the “tests” a t the rate of forty per hour. CLEANING THE SYSTEM- The object of running all the “blanks” first is to avoid interaction with traces of residual enzyme from the “tests.” At the end of the day, or next morning before further “blanks” are recorded, clean the system by pumping water for 5 minutes, N hydrochloric acid for 10 minutes and then water again for 5 minutes through all the liquid-conveying lines. CALCULATION OF RESULTS- Clip the chart of the “blank” records on the Simplon drawing-board, align it horizontally, and place the transparent plastic scale over the peaks for the standard solutions.With use of a calibration incorporating the dilution factor and the factor 1.53 (to convert micrograms of potassium phenoxymethylpeniciln to units), construct a graph on the chart paper relating potencies of the standards (in units per millitre) to mean chart readings. Maintain the scale in horizontal alignment, slide it over each “blank” record until the leading edge covers the top of the peak, and read the appropriate potency at the point where the scale cuts the graph. When the “tests” have been recorded, use the standards recorded on this chart to construct a graph from which the “test” potencies can be read in a similar manner. Deduct the “blank” from the “test” potency, and record the result as the “net potency” of the sample.(Omit the first set of standards on subsequent plates.) RESULTS AND DISCUSSION OF THE METHOD Typical test and blank recordings are shown in Fig. 4, the appropriate standards being at the left-hand side of each record; the calibration graphs plotted resemble that in Fig. 2. Results for samples of experimental shaken-flask fermentations for phenoxymethylpenicillin are shown in Tables I and 11. Similar results have been obtained for the assay of benzyl- penicillin fermentations. Results by the manual and automatic methods (turntable rate, forty samples per hour) are compared in Table I, which covers a potency range of approximately 2500 to 5000 units per ml. Variation in the amount of iodine absorbed by the “blank” clearly has a significant effect on the net potency; compare, for example, the results for samples Nos. 11 and 18.To calculate the standard deviation of the method, including dilution, and plate-to-plate variations in standards, “blanks” and “tests,” replicate determinations on twenty experi- mental broths were made, a fresh plate being used for each set. (All these samples were highly turbid, because of dispersed oil; the dilution, however, overcame interference from334 GOODALL AND DAVIES : AUTOMATIC DETERMINATION OF PENICILLIN [Vd. 86 TABLE I: COMPARISON OF RESULTS BY AUTOMATIC AND MANUAL Sample No. 1 2 3 4 6 6 7 8 9 10 11 12 13 14 16 16 17 18 19 20 21 22 23 24 26 “Test” potency, ‘ units per ml 4430 3550 4720 4920 4270 6380 6020 4680 6020 4260 6660 3430 4600 4220 6260 4490 4660 6660 6740 3840 4640 6640 6370 4620 4160 Mean 4746 ‘Blank” potency, units per ml 1280 1080 1260 1420 1270 1220 1040 1420 1200 1470 1280 1160 1360 980 1300 1080 1370 970 1270 960 1710 1160 1300 1490 1260 1251 Net potency, units per ml 3150 2470 3470 3500 3000 4160 3980 3160 3820 2790 4270 2280 3140 3240 4960 3410 3190 4690 4470 2890 2830 4490 4070 3130 2890 3494 METHODS Net potency by manual method, units per ml 3120 2205 3510 3450 2795 4055 4085 3075 3665 2686 4226 21 60 3090 3370 4705 3420 3000 4600 4395 2706 2890 4410 4180 2965 2796 3422 this source.) Aliquots from each sample were diluted, and the “blanks” were determined as described above.Fresh aliquots of each sample were diluted with enzyme solution, and, after 1 hour at room temperature, the “test” determinations were made.The total sequence was repeated, and the second plate of “blanks” was analysed before the first plate of “tests” to avoid reaction with any residual enzyme introduced into the lines at the “test” stage. Table I1 shows the results and Table I11 the statistical analysis. The standard deviation of 75 units can be expressed as 2.1 per cent. of the mean net potency of 3558 units per ml. TABLE 11: REPLICATE RESULTS FOR EXPERIMENTAL FERMENTATION BROTHS Net potency found in- Sample No. 1 2 3 4 6 6 7 8 9 10 11 12 13 14 16 16 17 18 19 20 fist series of assays ( A ) , units per ml 3690 2860 3360 3806 3866 3686 3636 3220 3536 3666 3120 3760 3996 3936 3656 3570 2950 3890 3555 3216 second seriis of assays (B), unils per ml 3615 2986 3480 3946 3905 3760 3690 3096 3630 3695 3260 3850 4060 3946 3630 3780 2766 3870 3700 3216 Difference umts per ml 26 126 120 140 60 76 (B - A ) , - 46 - 126 96 30 140 90 66 10 75 210 - 186 - 20 146 0May, 19611 IN FERMENTATION BROTH: AN IMPROVED IODIMETRIC ASSAY 335 This deviation includes a small bias (51 units between means) on the two sets of repeat determinations, which is the sum of the following deviations.The means of blanks 1 to 20 were (A), 1891 and (B), 1870 and of tests 1 to 20 were (A), 5424 and (B), 5453. This leads to a net positive bias in the (B) series of 21 + 29 = 50 units over the (A) series. Our working experience is that a standard deviation in the range 2 to 2.5 per cent. can be expected in the routine analysis of the type of broth already described. Tests with pure crystalline penicillinv have given results within 1 per cent. of the theoretical. TABLE 111 STATISTICAL ANALYSIS OF RESULTS IN TABLE I1 Sum of net potencies found- First series of assays, units per ml . . .. .. .. .. Second series of assays, units per ml . . .. .. .. Sum of differences (B - A ) , units per ml . . .. .. .. First series of assays, units per ml . . .. .. .. * . Second series of assays, units per ml . . .. .. .. Mean for both series. units per ml . . .. .. .. .. Sum of squares of differences, I: (B - A)' . . .. .. .. Mean net potency found- .. .. .. .. .. .. .. 1 x 223,350 40 Variance, 70,655 71,675 1020 3533 3584 3558 223,350 5583.75 Standard deviation, units .. .. .. .. * . .. 74.7 Standard deviation, as percentage of mean net potency for both series 2.1 Preliminary experiments in the same system at the higher rate of sixty per hour also We thank Mr. M. Gent, now of the Bradford Institute of Technology, for carrying out show promise. the statistical analyses and for helpful discussions. REFERENCES 1. 2. 3. 4. 5. Niedermayer, A. O., Russo-Alesi, F. M., Lendzian, C. A,, and Kelly, J. M., A n d . Chew., 1960, Pan, S. C., Ibid., 1954, 26, 1438. Green, N. C., and Monk, P. R., Chem. G. Ind., 1959, 1210. Bethel, M. M., and Bond, C. R., Analyst, 1961, 86, in the press. Ferrari, A., Russo-Alesi, F. M., and Kelly, J. M., Anal. Chem., 1969, 31, 1710. 32, 664. Received Octobev llth, 1960

ISSN:0003-2654    

DOI:10.1039/AN9618600326

出版商:RSC    

年代:1961

数据来源: RSC